The Fear of All Sums
by Samuel Marks
Summary: The opening story of Gallifrey Base's Novella Series, written to celebrate the 50th Anniversary of Doctor Who! The Fourth Doctor, Romana II and K-9 investigate when impossible events begin to occur all over the universe. Plus, a brand new Time Lord makes his first appearance. What is his connection to the Doctor, and why are people trying to kill him? Artwork by Philip Boyes.
1. Chapter One

The Fear of All Sums

By Samuel Marks

Chapter One

In Egyptian folklore, it was known as the Forgotten Tomb, but everyone remembered it. They were simply too scared to speak of it. The tomb was cursed, so the legends said, and anyone who dared to disturb the lost resting place of the ancients was doomed to live a life tormented by the gods.

"Pile them up, nice and high, that's it..."

Fear kept the local population in line. Inhabitants of the nearby villages undoubtedly knew more about the history of their land than they let on, though they still refused to share their wisdom or enlighten the desperate adventurers who came knocking at their doors. Many went home, reluctantly admitting defeat, forced to respect the wishes of the dead.

"Prepare the fuse, and fetch the matches..."

Some, however, refused to give up so easily. Nothing was ever truly forgotten. Anything could be found if you looked hard enough. There were always traces left throughout history, a trail to follow to your goal, footprints in the sand.

"Strike it, and let the flame burn..."

Not even talk of terrible myths and dreadful curses was enough to deter the most resolute, or perhaps foolhardy, explorers. After all, the threat of gods ruining your life only worked if you had a life worth ruining.

For history professor and part-time adventurer Harold Cartwright, there was nothing left to lose. Everything that the world could take from him had already been stripped away. He did not fear the gods; he challenged them.

"Now... Light it up!"

Harold had recruited a small band of greedy and foolish Egyptian youngsters to accompany him on this expedition to where he believed the Forgotten Tomb was hidden. One of these poor, unfortunate souls had been tasked with blowing a hole in the side of the mountain, creating an entrance. Having been unable to locate the front door, Harold had decided to make his own way in.

He had placed stacks of dynamite against the rocks, with a single fuse ready and certainly able to detonate them when lit. What little money he had left had been spent on this expedition. For Harold, everything depended on it.

He watched, from a safe distance of course, as the Egyptian man who was being paid to put himself in danger held the lit match in his trembling hand. Harold whipped off his hat and lightly fanned himself, uselessly trying to fight back against the suffocating heat.

He watched with bated breath, knowing that any minute it was about to get a whole lot hotter.

But then, as the match was moved closer to the fuse, the strangest thing happened. Out of nowhere, a mighty gust of wind blew through the valley, extinguishing the flame mere moments before it could explode the mountainside.

The hireling turned to Harold, with fear in his eyes, desperate for guidance.

"Again," Harold said firmly. He knew that a similar breeze could not inexplicably scupper his plans for a second time.

Well, he _thought_ he knew...

Once again, at the last minute, the flame died.

"Again, again, again..." said Harold, with increasing desperation, as every single match in the entire box was extinguished one by one by a seemingly supernatural wind.

Harold marched over to the hireling in charge of the explosives, but the man hurried off into the distance at a considerable speed. When Harold looked around, he saw that the other recruited locals had fled, seemingly believing that the curses of the Forgotten Tomb were coming true. It certainly seemed as though higher powers were preventing its discovery, warning off the unwelcome travellers.

Now all alone in the middle of nowhere, he dropped to his knees and began to cry. He had come so close, having battled his way through ancient myths and desolate landscapes and irritating customs, and yet had been thwarted by the wind of all things. Perhaps, he considered, everyone he had ever known had been right to call him a failure, a walking disaster, a fool.

Harold took off his glasses and rubbed his eyes. Wiping the tears away, he wondered whether he might be able to use his spectacles to magnify the harsh sunlight and direct it onto the fuse. He had always hoped that his short sightedness might benefit him one day—but no, it seemed there was no way of doing it.

Harold then spent the rest of the day feeling sorry for himself, and he had almost given up hope entirely. It was only as he searched through his rucksack, hoping to find a few drops of water remaining in his flask, that he found his set of tent pegs. He wondered if that just might work, whether they could be enough to start a fire and ignite his dreams. With nothing else to lose, Harold thought it was worth a try.

Had he really been reduced to this, he wondered? Rubbing sticks together like a savage? He bemoaned his dreadful luck and how nothing ever went to plan.

But then, for the first time ever, it did.

Sparks burst forth from between the two writhing sticks, erupting into a magnificent and glorious fire that burned stronger and brighter than the setting sun.

The flames lit up the fuse. Harold was delighted and jumped for joy, and it was only when he realised that he was about to be blown to smithereens did the smile fall away from his face. He ran for his life.

The explosives did their job and detonated with tremendous force, destroying a good chunk of the mountainside. Harold was knocked off his feet as he fled in the opposite direction, landing in the dirt. He covered his head, shielding himself as rocks and debris from the blast rained down.

Calmness and silence returned to the secluded corner of the Egyptian wasteland. Harold clambered to his feet and gazed in awe at the newly created hole in the mountainside. He caught a glimpse of what looked like something shiny in the darkness, and he allowed himself the biggest smile.

He had found it, finally; he had found the Forgotten Tomb.

Slipping through the crack in the rock, Harold found himself in what appeared to be the burial chamber. He had managed to create a narrow path that took him straight to the diamonds and jewels and treasures of the ancient world, lost for centuries, shrouded in myths and secrecy. Just one of these, Harold knew, would change his life.

Harold brushed the cobwebs aside, wiped dust from the sparkling jewels that had gone untouched for so long. Yes, there was no doubt about that. The place was so clearly undisturbed. He revelled in the knowledge that he had been the first man to stand in this chamber and look upon these treasures for centuries. But regardless of the priceless artefacts surrounding him, it was the sarcophagus in the centre of the chamber that demanded his attention. Overwhelmed by its beauty and magnificence, and by what it meant to him and his life, tears filled his eyes.

He had waited for this moment his whole life. He had shown everyone who ever doubted him that he was not sad or pathetic or mad.

He was definitely _not_ mad.

That was what Harold told himself, repeatedly, despite what happened next. A ringing sound filled the air. Not expecting to hear such a noise in the Forgotten Tomb—which had not been disturbed in any way for thousands of years—it took Harold a few moments to realise that it was the ringing of a _tele__phone_ that he could hear.

And it was coming from inside the sarcophagus.

He took hold of the lid, lifted it off and let it fall to the floor of the chamber with a crash that echoed around the ancient halls. Inside the sarcophagus was a mummified body, which Harold had been expecting, and something else that he had not.

It was a telephone, that was for sure, but it didn't seem to be connected to anything. Not that Harold had been expecting wires or anything of the sort in an Egyptian tomb, but neither had he expected to find a telephone. Now that he had, he at least expected it to adhere to common sense. Telephones needed electricity, but this one seemed somehow... _mobile_.

Harold prised the phone out of the grasp of the mummified fingers and looked at it. The ringing continued.

He studied the object, wiping thousands of years' worth of dust off the screen. The words _Unknown Number_ flashed up—that was about right. Who would be phoning a corpse? And how would a mobile phone have existed in Ancient Egypt to be buried with a dead man? Harold didn't know the answers, but he was going to find out.

He pressed a green button on the telephone, which seemed to do the trick, and held the contraption to his ear. "H-hello?"

A booming voice assaulted his ear, so he moved the telephone further away.

"How did you get this number?" Harold could barely hear the reply through the static. It was a very bad line. "What? I'm sorry?" He listened intently to find out the identity of the caller. He didn't understand...

"Doctor who?"


	2. Chapter Two

The Fear of All Sums

By Samuel Marks

Chapter Two

ARCHAEOLOGIST ADMITTED TO PSYCHIATRIC INSTITUTION stated the newspaper headline. Romana barely gave it a moment's consideration as she flicked through the pages to pass the time. She set the paper down beside her on the park bench, and squinted up at the midday sun. It shone down on her and she bathed in its warm glow. Romana found herself smiling at the unexpected beauty of planet Earth.

"This is perfect," she said to herself, seconds before a tennis ball hit her square in the face. Rubbing her sore nose, she looked up.

"Sorry, Romana!" The Doctor was calling over to her from across the park. He smiled apologetically.

Romana reached down and picked up the tennis ball from the grass at her feet. Swinging back, she threw the ball out towards the Doctor. It wasn't a bad throw, but nonetheless it didn't reach him.

Instead, the ball was caught in mid-air by a scruffy, brown-haired dog. His teeth snapped around the tennis ball, and he carried it over to the Doctor. Setting it down at the man's feet, the dog barked excitedly, his tongue hanging out of his mouth.

"Good boy, K-9!" grinned the Doctor, as he patted the dog on the head.

Watching this from afar, Romana allowed herself a smile. A few days ago, she would never have imagined that K-9 would spontaneously transform into a real, proper dog. It had certainly taken her and the Doctor by surprise when K-9 had seemed to explode with white light inside the TARDIS, becoming a far more traditional dog that he was ever manufactured to be.

Romana put the newspaper under her arm and made her way over to the Doctor and K-9. As she watched the man and dog playing happily, she almost couldn't believe her eyes: the two of them were actually getting on and having a great time together. Never in a million years did she think _that_ would happen.

"You're not at all concerned about this?" she asked, indicating the living, breathing, barking version of their old metal dog.

The Doctor laughed. "Of course not, Romana. Don't you remember how K-9 used to behave? Always showing off and correcting me and making me look stupid?"

Romana nodded.

"Well, look at him now." The Doctor picked up the tennis ball and pretended to throw it across the park. When K-9 hurried off in pursuit of nothing at all, the Doctor exploded with laughter.

"You're enjoying this far too much," smirked Romana. "We have to find out _why_ he changed like this. It can't just be an accident."

The Doctor shrugged. "Stranger things have happened."

Romana couldn't argue with that. If the Doctor wasn't worried, she decided, then she shouldn't be either. She was having too nice a day to waste it fretting about a dog.

K-9 trotted back over to the two of them, his tail between his legs. He whimpered at the sight of the ball, still in his master's hand. K-9 rolled over, and the Doctor started tickling him.

Romana found her gaze wandering around the rest of the park as the man played with his best friend. She smiled as she saw a young, happy couple sat together, eating from a picnic basket. Elsewhere, a man was teaching his son how to kick a football, and a mother nursed her baby in the shade.

She was enjoying watching people indulging in simple pleasures, and almost found herself longing to join in, when something else caught her eyes. Hanging from the branch of a tree, standing out against the beauty of nature, was a clunky piece of machinery: a security camera.

Romana looked closer, and knew that the lens was looking at her, too. "Preposterous," she muttered under her breath.

"What's wrong?" asked the Doctor casually, as he rubbed K-9's belly.

"Look at this." Romana tapped the Doctor on the shoulder and demanded his attention. But when the two of them turned back to the tree, the security camera was gone.

Confused, Romana said, "But I thought I saw..." Beneath the tree, a shadow stirred. Something was there, and then it was gone.

"Romana?" asked the Doctor. "What did you see?"

"Nothing, I suppose." She shook her head, dismissing it. A trick of the light, it must have been. "But I could've sworn..."

The Doctor put his arm round her. "Whatever it was, it's gone now."

"Yes," said Romana, "but gone where?"

Seemingly uninterested, the Doctor plucked the newspaper from under Romana's arm and flicked through it, reading every page in an instant. "Slow news day," he said to himself. But something must have caught his eye, as he rapidly turned the pages in search of something.

K-9 yapped at his feet, desperate for attention, and Romana scratched the dog behind the ears.

"Look at this," the Doctor said, as Romana peered over his shoulder at the newspaper. "A new art gallery has opened up today, just around the corner. Fancy a look?"

Romana nodded. "Of course." She put her arm through the Doctor's, as they turned to walk out of the park.

They made their way across the town to the art gallery, and left K-9 outside tied to a lamppost. The dog let out a high-pitched whimper, clearly unhappy at being left on his own, but the Doctor already seemed tired of his suddenly furry friend.

Romana followed the Doctor into the gallery, and stood at his side as they studied various paintings. But when the Doctor decided to tell her the story behind every single one, which usually featured himself in a starring role, she wandered off and explored on her own.

There were paintings from through Earth's long and great history, remarkable compositions of incredible beauty. Romana was enraptured. Humanity really was a grand species, as the Doctor always insisted. She no longer wondered why he loved this planet so much.

As she wandered around the silent, empty halls of the gallery, one painting in particular caught Romana's eye. The sign next to it declared that it was called the _Laughing Cavalier_, and that the man it depicted was something of an enigma. Painted in 1624, the subject was clearly a military man, dressed in elaborate and beautiful clothes. His smile was charming and his eyes were alluring. But it was more than that...

Romana leaned closer to the frame. There was something else about the painting, but she couldn't quite place it. The secret was in the eyes, she knew that, but what was it?

"Recognise him?" asked the Doctor.

Romana jumped in fright. He was stood right behind her, and no doubt had been for some time. "What do you mean?"

The Doctor indicated the painting. "You know him. So do I."

Romana thought hard. That was it: the eyes were _familiar_. "He's a Time Lord!" she realised aloud. "I remember him from Gallifrey. Well, I saw pictures of him. We never actually met."

The Doctor stared straight ahead, as if lost in thought. "We were in the same classes at the academy. Both dreamed of running away someday, to go off and explore the universe. He was something of a history buff, always had his head buried in textbooks, reading about some battle or war."

"Did he succeed in running away from Gallifrey?"

"Of course." The Doctor nodded at the painting. "Stole a TARDIS just like I did, and ran for the stars. He made it to Earth, to join in the English Civil War. But he must've arrived too early, by about two decades, and got his portrait drawn to pass the time. That's what I heard, anyway. Look at him, smiling out at us from that frame. What a guy!"

Romana was remembering more and more now. "Don't they call him the Cavalier now, back home?"

"That's his identity. Suits him, I think. He always was so confident, always in a hurry, never thinking things through. When the Time Lords found out about this painting, how he had gotten involved in the affairs of this planet, they exiled him. Stripped him of his name, labelled him as the Cavalier to remind him of his crime, and told him never to return."

Romana noticed to wistful look in the Doctor's eyes. "When did you last see him?"

The Doctor shrugged. "Ages ago. Too long, I think. But the universe is a big place, Romana. We're hardly likely to bump into each other. And I never was very good at staying in touch with people."

"That's a shame."

"Yes, it is." The Doctor smiled absent-mindedly, lost in thought. "We were close, back in the day."

Romana was suddenly reminded of the rumours that had circulated the Prydon Academy long after the Doctor's time, of graffiti on the walls, of names scratched into tables. "Some would even say _too_ close," she grinned.

The Doctor feigned offence. "Romana, we were youngsters! At school! There was no time for any of that nonsense, was there? What would make you think I wasted my time like that?"

"Well, passing your finals with fifty-one percent on the second attempt might be seen a small clue—"

Harsh, blaring sirens interrupted Romana. Instinctively she grabbed hold of the Doctor's hand. He was frozen to the spot, looking around frantically, eyes wide. He wasn't scared; it was more like excitement.

All of a sudden the noises stopped the lights went out. The whole gallery descended into total silence and darkness. Romana could see nothing. She squeezed the Doctor's hand tighter. "What's happening?" she whispered.

The Doctor gave an answer that always made Romana feel uneasy: "I don't know."

A few tense moments passed before the lights snapped on again. Romana looked around to see what had happened, but nothing seemed to be wrong. Everything was as it was, except for one thing...

The _Laughing Cavalier_ was gone.

"Now why would someone want to steal that?" the Doctor wondered aloud.

Romana could only shake her head; she had no idea. Looking up at the Doctor, she saw that he had broken out into a huge grin. Adventure had found them, it seemed, and he loved it.

Before she knew it, Romana was smiling back. "Shall we go in search of it?" she asked, but the Doctor was already running off down the corridor, his never-ending scarf trailing behind him as he went.

"Come on, K-9," cried the Doctor, as he burst out of the art gallery. "Walkies?"

A few paces back, Romana wasn't sure why he had voiced that last word as more of a question. But when she looked to where the dog was waiting, she understood: K-9 was now back to his old self again.

The Doctor untied the robot dog from the lamppost, and studied his metal companion intently. "You changed back," he said simply. The disappointment in his voice was clear.

"I am well aware of that, Master," replied K-9.

"I liked you before," the Doctor said. "You answered back less. You weren't so sarcastic and condescending. You were politer and more fun and, you know, _fluffier_. Why couldn't you stay as you were?"

"It was not in my control," said K-9. "All systems have now been restored to their original functionality."

"That's a shame." The Doctor wore a miserable look on his face. "Come on, then," he sighed. "Let's get back to the TARDIS. We've got a painting to find—"

Interrupting him, K-9 barked.

Romana snorted. "K-9, did you just...?"

The robot dog didn't answer for a moment. "Side-effects are to be expected."

The Doctor rubbed his hands together with glee. "Oh, this is going to be fun!"


	3. Chapter Three

The Fear of All Sums

By Samuel Marks

Chapter Three

Hidden in the shadow of the Alps, in the year 218 BC, was a Roman encampment. A dozen tents had been erected on a small perch on the mountainside, protected from the harsh winds and concealed from view by the tundra.

General Lucius Vispanius Titus the Wise, Commander of the Army of the Alps, Recipient of the Golden Eagle and Sigil of Remus, Defender of the Empire, sat alone in his tent. He was deep in thought, contemplating his strategies for the forthcoming battle. On this day, the mighty Empire of Rome was relying on him to command a small band of soldiers to victory. He had ordered them all to get a good night's rest, but he had been unable to follow his own orders.

Warfare didn't usually bother General Titus. His ancestors had been great leaders, and their courage and wisdom were in his blood, but he couldn't help but feel slightly overwhelmed by the pressure he was faced with. He knew what was coming for Rome, and it was all down to him to stop them.

He was leaving nothing to chance. His battle plans had been meticulously outlined with painstaking precision. He would not allow any silly mistakes to cause their downfall. General Titus could not, however, have predicted what was about to happen.

A fresh-faced Roman soldier came hurrying into his tent, out of breath and clearly panicked by something.

"What is it, soldier?" asked Titus.

"A man, sir. A man's been sighted crossing the Alps!"

General Titus gulped. Was this it? Had the battle begun earlier than expected? Their information had never been wrong before, but perhaps this was a sign that the gods were not on their side.

"Is it... _him_?" he asked. A name was not needed; they were all thinking of the same person. He was the only man they had thought of for days, the same man who haunted their dreams.

"No, sir," said the soldier. "It's a stranger in these lands. And I think he's dying..."

The Alps were a treacherous path, Titus knew, and anyone who dared to traverse their wintry heights was brave indeed. That was why the Empire feared their current foe so much, almost respecting and fearing him in equal measure.

But if someone else had dared to challenge the mountain, they did not deserve to die alone in the terrible silence of these wintry heights. A dignified death was the least that Titus could do for the unknown wanderer. And perhaps, after this act of unprecedented kindness, the gods might smile upon him in the coming conflict.

He ordered the soldier to escort the man off the mountain, out of sight, and to bring him down to the General's tent, which was acting as the official command centre of their field base.

General Titus watched as the man was carried into the safety of the tent, and ordered that he be placed upon his bed to keep him warm. The stranger looked in a bad way. He could not speak; his lips were blue and quivering; his whole body was trembling; the snow and the winds had caused his skin to turn paler than anything that Titus had ever seen before.

Titus knew that the man would not survive for long. He had, at most, a few minutes of life left to cling onto before darkness claimed him forever more. "Be brave, sir," said Titus. "Do not fear death. Embrace it!"

The man's eyelids—previously frozen shut—slowly began to open, as did his mouth. He strained, struggling to speak, before he eventually managed it. "No can do, amigo," he mumbled. "You might want to step back..."

Confused, General Titus did as he was told. Fearing what might happen, he ordered all other soldiers to leave the tent, and watched alone as the most remarkable thing happened. The stranger's body began to glow with a strange, ethereal light. The warmth that seemed to burn from within melted the snow that clung to his skin, and he once again looked healthy.

General Titus suddenly noticed the extravagant clothes that the man was wearing—and the only reason they grabbed his attention was because they too melted away from him as the light that shone from beneath his skin began to burn harsher and brighter. His flesh seemed to be on fire. Titus wondered whether the man's body was simply going to melt away just as his clothes had. The General was forced to shield his eyes as the bizarre, supernatural event became unbearable to watch. He heard the man cry out in pain and could do nothing to help.

Then the light died, and the man didn't.

Slowly, General Titus allowed himself to gaze upon the man again—but it seemed that he was gone, and had been replaced by someone else. This new man leapt up off the bed and started looking himself up and down.

"Let's see what I've got this time," he said. "Twelfth time lucky, I hope..."

General Titus could only watch in horror, and with mild amusement.

"Oh, look at that belly!" said the man. "I'm fat! And already hungry! I can barely see my feet. Oh, and I wish I hadn't looked—they're so small. I reckon about a size four. That'll make shoe shopping a big tricky, but not impossible. I wonder if certain other extremities are similarly undersized... What do you think, General? Not a bad size, eh? And hey, it's what you do with it that counts, am I right?"

Titus leapt to his feet, suddenly realising how absurd the whole situation was, and drew his sword. He held it up to the man's neck, pressing lightly upon him—but he was willing to press harder. "I don't want to spill any more blood than is necessary today," he warned, "so you had better explain yourself, stranger—"

At that moment, another Roman soldier entered, quickly looking away when he noticed the man.

"It's all right," the man said, putting his hands on his hips and standing proud. "You can look. And I'd be interested to hear your opinion on it. Good or bad? Average?"

"Below average," sneered General Titus, much to the man's annoyance.

"Sir, there's a naked man in your tent," said the Roman soldier matter-of-factly.

"Yes there is, so why don't you get him some clothes?"

The man nodded and left, no doubt emotionally scarred by the brief experience.

General Titus lowered his sword and sheathed it, inviting the man to take a seat—on the floor, not on the bed. People would talk, and he had a reputation to think of. "Start at the beginning," he said, "and tell me everything. Who are you?"

"I," said the naked man, "am the Cavalier."


	4. Chapter Four

The Fear of All Sums

By Samuel Marks

Chapter Four

The Cavalier's head was spinning. He could barely remember his own name, let alone that of the man who had helped get him to safety. Was it Titan? No, Titus, that was it. The man—General Something Fancy and Unpronounceable Titus—handed the Cavalier a suit of Roman armour to protect his modesty and to prevent any further awkwardness between the strangers. Their hug a few moments ago had been bad enough. It was only awkward for Titus, of course. The Cavalier had rather enjoyed it.

He could fell regeneration energy dancing around his body and, though it would stay with him for a good few hours yet, it was becoming less effective at combatting the cold. As such, the Cavalier was glad to get dressed and shield himself from the harsh winds. He may not have liked his new body on first impressions, but he had to look after it. He had become rather careless with his bodies of late, and he couldn't afford to be like that anymore, much to his annoyance. Being careful wasn't usually much fun at all.

General Titus took a seat in front of the Cavalier, and smiled reassuringly. He seemed like a good man, the Cavalier thought. Tough and butch and not really his type at all, but a good man nonetheless. A soldier. A man of war. The Cavalier had met plenty of those, the best and the worst. But never had one been so kind to him as Titus had been on this day.

"Thank you," said the Cavalier. "For saving me."

"That's quite all right," replied Titus. "Thank _you_ for putting some clothes on."

The Cavalier nodded. Out of the corner of his eye, he thought he noticed something. There was something amiss in this tent. Something _wrong_. He could feel it in his bones. His Time Lord senses were tingling, but he couldn't quite place what it was. He rubbed his eyes and looked around. And then he saw it. In the corner of the tent. A machine. An actual piece of working machinery in Ancient Rome. Something out of time...

"Now, stranger, we have lots to discuss—"

"What is _that_?" asked the Cavalier, pointing in the direction of the anomaly.

General Titus rose up out of his seat and crossed the room, reached the machine before the Cavalier. He threw a large piece of fabric over the machine, concealing it from the Cavalier's view.

"It's a distraction, clearly," said Titus. "Please, sit down, stranger. Tell me how you came to be wandering the Alps, and how you happened to... _not die_."

The Cavalier noticed a determined look in General Titus' eyes. The Roman clearly wasn't going to rest until he knew the truth. As much as the Cavalier wanted to find out about the strange machine, he did as he was told and sat down. The Cavalier took a deep breath, filling his brand new lungs with the cold mountain air, and began to speak.

"I was being followed by someone," said the Cavalier, "through the Time Vortex. Their ship had a trans-dimensional warp drive that meant they could follow me right across the dimensions, through supernovas and black holes and loops in the causality nexus that I thought might cancel out the tracking signal on my TARDIS. But I couldn't shake them.

"So I materialised here," he went on, without stopping for breath, "close to my intended destination, somewhere in the Alps. And as the chameleon circuit was doing its job, my TARDIS suffered a direct hit from their anti-matter cannon. My ship—my home—was completely obliterated. I narrowly escaped the same fate. I was weak; I was hurt. So I ran, luckily found your camp, and managed to regenerate. Completely rewrote my biology and managed to live. Understand?"

"Not completely," said General Titus. "Not much, in fact. Your enemy... Is he the same as ours? Are you facing the wrath of Hannibal of Carthage?"

"Nah," said the Cavalier. "Could be anyone after me. In my travels, I tend to upset a lot of people..." But then he realised that something was amiss. Something _else_... "Hang on," he said, "how do you know that Hannibal is coming for you?"

The Cavalier had intended to come to Ancient Rome at this time to witness the famous point in history where Hannibal, enemy of Rome, lead his forces across the Alps to launch a dangerous surprise attack against the Roman Empire. So, he wondered, how could they possibly know that the attacker was on his way?

"We have the greatest minds in the known world working for us, sir. They have created wondrous technology that gives us the gift of foresight, amongst many others things."

Could that be what the strange machine was for? "Show me now!" the Cavalier demanded.

General Titus unveiled the machine in the corner of the tent. The Cavalier found himself trembling as he approached it, because he knew what it was, and therefore he knew what it meant. "What have you done?" he asked, noticing terror in his own voice. "And, you know, _how_?"

The Cavalier found himself looking at what was unmistakably a computer screen, upon which a map of the surrounding area was displayed. It was covered with tiny dots, each representing one of the forty thousand men that were under the command of Hannibal—along with their accompanying party of elephants—who were coming to attack the Roman Empire.

"Is there a problem?" wondered Titus.

"This is a radar," said the Cavalier. "And this is very, _very_ wrong..."


	5. Chapter Five

The Fear of All Sums

By Samuel Marks

Chapter Five

"Come on, K-9," said the Doctor, stepping out of the TARDIS.

Romana followed, too, as K-9 led the way. His sensors had detected a faint trace of teleport energy around the gallery, and so they followed the perpetrators to this location. Romana looked around to see where exactly they had ended up. She couldn't help but be a little disappointed.

The grey walls and lifeless corridors were frankly a little boring compared to the intellectually stimulating environment of the gallery. Not to mention the heat—it was ridiculously hot in this place. Romana whipped off her jacket and carried it under her arm as she followed the Doctor. Either he didn't notice the heat or simply didn't care, as he continued to wear his scarf and heavy coat and seemed as carefree as usual.

"Where are we, Doctor?" Romana asked eventually.

"Still on Earth," the Doctor replied. "Not sure exactly where. Looks like a factory of some kind. Now where is that painting? It must be close..."

Romana couldn't keep up with the Doctor's huge strides as they wandered through the corridors. This building—whatever its purpose—seemed to grow hotter and hotter the deeper into it they went. A bead of sweat tumbled from Romana's forehead and hit the floor with a hiss.

There was not a single other sound as the trio made their ways through empty corridors and hallways in search of the painting. However, despite the Doctor's assertions, there was no sign of it.

Romana went to put her arm through the Doctor's, but he seemed more concerned with searching out a bag of jelly babies from his pockets. That brought a smile to his face, as he greedily and noisily ate his way through the whole lot. Romana sighed: the last thing she needed was for the Doctor to become even _more_ hyper than usual...

Disappointed to find that he had finished the bag rather sooner than he had expected to, the Doctor casually dropped the paper bag on the floor.

Immediately, sirens rang out. The Doctor, Romana and K-9 all froze, looking around to see what was wrong and covering their ears from the blaring, deafening sound.

"An alarm has been triggered, Master."

"Thank you, K-9. How would we ever know that without you?" He voice was dripping sarcasm, but K-9 didn't seem to notice as he wagged his metal tail happily.

The sirens continued wailing for a while longer, before a voice filled the air, taking its place: "A crime has been committed. Remain where you are. You will be apprehended shortly. Justice will be swift."

Romana realised that the words seemed to be coming from a security camera that was mounted on the ceiling. It seemed to be identical to the one she had glimpsed in the park earlier. Before she could raise the point, the Doctor exploded with laughter.

"Silence! You _will_ be apprehended!" the voice repeated.

"Oh, big words from a little camera," said the Doctor, still chuckling. "Who's coming to get me? The police?"

"Camera 4-6-5 will make the arrest."

"Is that _you_?" asked the Doctor. "_You're_ going to arrest me? How do you plan on doing that, then? By growing little legs and jumping off the wall?"

The Doctor was, unintentionally, absolutely right; that was exactly what the security camera did. From the side of its bulky body, where the camera itself stared out, two thin mechanical legs unfurled themselves, and the machine detached itself from the ceiling. It landed on the floor, a short distance away from the Doctor, and looked up at him with its one large lens that acted as an all-seeing mechanical eye.

"That's ridiculous!" cried Romana, stifling a laugh. "Totally and utterly ridiculous!"

"Oh, good idea," the Doctor replied sarcastically. "Make it _more_ cross!"

The trio began to back away slowly, and the walking, talking security camera's little legs struggled to keep up with them. "Halt! You are under arrest! Justice will be swift!"

"He only dropped some litter. Can't you be a little lenient?" pleaded Romana. "It's hardly the crime of the century, is it?"

The camera's eye began to glow, as it scanned the Doctor. "Incorrect," it said. "You are the Doctor. Previous offences include seventeen counts of planetary destruction, four counts of kidnap, and three-hundred and ninety-one counts of illegal parking."

"I've got a permit!"

"Resistance will not be tolerated!"

The camera began to spark with electricity, and what looked like bolts of lightning burst out of its lens. They struck a flickering light bulb on the ceiling, and glass shattered at Romana's feet. As absurd as these little cameras were, she thought, they packed a hell of a punch.

"Hang on," said Romana. "I'm sure we can be civil and resolve this without shooting—"

Romana ducked as a second bolt was hurled at her. She had avoided it, just about. But K-9 was not so lucky. The third bolt struck him on his side, and electricity crackled around its whole body before the robot dog froze completely still. Defunct. Broken.

"Hey! That's my dog!" the Doctor cried out.

"Collateral damage is permitted in pursuit of a felon, but surrender is preferable."

"Never!"

"Doctor, we should run," Romana whispered.

The Doctor nodded. "Hey, look!" he said, pointing behind the camera. "It's Mussolini! And Hitler! Robbing a sweet shop!"

As the camera twisted around, the Doctor picked up K-9, and he and Romana ran as fast as possible in the opposite direction. They sped down the long, twisting corridors, which all the while seemed to be growing hotter. But Romana was more concerned with the camera.

"Have we outrun it?" she asked, almost out of breath.

"I think so," replied the Doctor.

They stopped to get their breath back, and as they did, Romana spotted something through a hatch in a nearby door. Calling the Doctor over, they saw the _Laughing Cavalier_, discarded on the floor of an empty room.

"Why would the thief just leave it here?" Romana wondered aloud.

Keen to find out, she and the Doctor heaved the door open and stepped through. The Doctor studied the broken K-9 while Romana examined the painting. It looked in fine condition, as far as she could tell, but she still couldn't understand its abandonment, nor could she find clues to identify the thief.

Romana also found the heat in this room to be almost suffocating. It couldn't just be her, she reasoned. The Doctor must have noticed it, too.

"Are you really not feeling the heat?" she asked him.

The Doctor seemed to think for a moment. "Yes, now that you mention it. Mind you, that's probably because of what this room is for."

"What do you mean?"

"Haven't you seen the signs? This is an incinerator."

Romana felt her jaw almost hit the floor, and the Doctor only seemed to realise the impact of the word as it left his mouth.

"Incinerator?" Romana asked, hoping that perhaps she had misheard.  
"Yeah," the Doctor replied nervously.

Romana instinctively looked to the door to make a run for it—but it swung shut before she could reach it. She heard a familiar scuttling sound outside.

"It's that little camera. He's shut us in!" She tried to the door, but it wouldn't budge. "It's locked. Well, of course it is."

"Easy," said the Doctor, as he reached for the sonic screwdriver. He tried the device on the locked door, but nothing happened.

"Problem?"

"Not so easy." The Doctor tucked the sonic screwdriver away. "Deadlocked."

Romana looked at the Doctor, but he simply shrugged. Neither of them had any ideas, it seemed. They were trapped in a room that was getting hotter by the second. Romana thought hard, but could come up with nothing.

"Oh, I know!" cried the Doctor excitedly.

"What is it? A plan?" Romana couldn't hide the joy in her voice.

"I've just realised what this place is. It's a disposal plant!" When Romana glared at him, he added, "I bet you want to hit me, don't you?"

Her clenched fists must have given it away, she decided.

"Affirmative! Affirmative! Affirmative!" cried K-9 frantically, as the robot dog regained his mechanical senses.

"Ah, back with us, K-9?" asked the Doctor warmly, patting the dog on its head. "Good. Just in time to die..."


	6. Chapter Six

The Fear of All Sums

By Samuel Marks

Chapter Six

As a Time Lord, the Cavalier had a kind of sixth sense when it came to disruptions in Time. But even without such an innate ability, it wouldn't have taken a genius to work out that a computerised radar did not belong in Ancient Rome. The Cavalier turned to face the Roman General Titus, desperate for answers.

"How can you possibly have this sort of tech?"

"The Roman Empire is widely recognised as the most powerful and technologically advanced civilization in the world," General Titus replied simply. He indicated the machine in the corner of the tent. "This is pretty basic, though. The satellites in the sky provide us with a detailed map of all life forms in the surrounding area."

"Sorry, satellites?" repeated the Cavalier in disbelief. "This is impossible!"

"It might seem like magic to you, sir. I imagine they do not have this where you come from." He looked the Cavalier up and down. "Come to think of it, where _are_ you from?"

"Gallifrey."

"Is that in Ireland? Yes, I think so. I have a friend in Ireland. We talk all the time on Skype."

The Cavalier shuddered. Nothing was as it was supposed to be. This was not the Ancient Rome that he had been expecting. He had planned to come to this day, in 218 BC, to see the Roman Empire taken by surprise by the forces of Hannibal, who had braved a dangerous fifteen-day trek across the Alps to attack unexpectedly from the north. Events had spiralled out of control for the Cavalier, of course, when he was attacked...

And then he remembered.

Post-regenerative trauma had apparently caused a very important matter to slip his mind, as the Cavalier only then remembered that someone had been following him, desperate to kill him. He needed to get out of here, to get home. But, as his malfunctioning mind told him, his TARDIS had been destroyed.

He was stuck in Ancient Rome.

And to make matters worse, it was the _wrong_ Rome.

Romana couldn't believe her dreadful luck. The day had started out so promisingly, with she and the Doctor spending a relaxing morning in the park. Sure, K-9 had randomly transformed into a _real_ dog—and then back again a few hours later—but that wasn't particularly unusual considering what life in the TARDIS was usually like. It was only when they had visited the art gallery that things had taken a turn for the worse.

When a painting mysteriously disappeared in the blink of an eye, the Doctor had taken is upon himself to head off in pursuit. K-9 had tracked it to this place—to the very room that Romana was now trapped in. An incinerator. Why did the Doctor always have to get involved in these things?

"Well," said the Doctor, holding the recovered painting close to his chest, "look on the bright side."

Romana glared at him. They were about to be burned alive—there _was_ no bright side.

"At least we found the painting," the Doctor finished feebly.

Romana shook her head, despairing. The room was getting hotter by the second. Flames were bursting forth from beneath the grates that they were standing on. In a few moments, their lives would end. The painting of one of the Doctor's old friends from Gallifrey—the _Laughing Cavalier_—wasn't going to be much comfort to her.

Romana braced herself. This was the end. "Goodbye, Doctor. Thank you for showing me what I never knew existed. Goodbye, K-9. You really were a good dog."

"As were you, Mistress."

Though she was offended, Romana was more interested in the Doctor's demeanour: he was strangely calm given the life-threatening situation.

"What's wrong?" she asked him, her curiosity prevailing even in the face of death. "Or rather, what _isn't_ wrong? You do know we're going to die, don't you?"

"Always so pessimistic, Romana!" said the Doctor. "Now, punch me in the face."

Without hesitation, she punched the Doctor as hard as she could, landing a harsh blow right on the nose, causing him to stagger backwards, recoiling with the pain. A small amount of blood trickled down his top lip.

He wiped it away, staring at his blood-stained hand in disbelief. "You... You _actually_ punched me!"

"You told me to!"

"I didn't think you'd agree to it quite so easily! You didn't even ask _why_! I had a whole speech prepared and everything!"

"Oh, but regardless, it made me feel so much better," replied Romana playfully. "I think, perhaps, I can die happy now."

"Maybe you can," said the Doctor, smiling through the pain, "but it won't be today."

The temperature began to rapidly decrease in the incineration chamber, as the three time-travellers breathed a sigh of relief—both literal and metaphorical depending on whether they were robotic dogs or not.

"We're not dying!" Romana cried, embracing her Time Lord friend. "How did you get us out of that problem?"

"By giving us another one," the Doctor replied gravely.

The exit door unlocked and swung open, and the sentient security camera hopped over the inch-high threshold to join them in the incineration chamber.

"Incineration has been prevented," it said. "A crime was detected in this vicinity, namely one count of assault. Death is not a valid excuse. Justice will be swift."

The Doctor, seemingly ignoring the security cameras remarks, knelt down to get a better look at the robot.

"K-9," he said, "have you got any information on these things? What exactly are they? Who created them, and why? I'd like to know who's to blame. And most importantly, do they have an off-switch?"

"Accessing files," said K-9, who appeared to be more helpful after his recent reboot. "These are the Kuricams, Master."

"Kuricams? What does that mean?"

"They are the future of policing. Not only do they see crimes being committed and record them for future reference, they are sentient and therefore able to carry out the arrests themselves. They are armed with lasers capable of stunning their target, and contain teleport technology to transport prisoners to their holding facilities."

"What a silly idea!" said the Doctor. "It's hardly fair. I mean, how are you supposed to convince these things that you won't misbehave again, in exchange for being let off with a warning? At least with flesh and blood police you can turn on the charm. You can't _flirt_ your way out of a crime when you're charged by these things."

"Well," said Romana, "_you_ can't..."

She glanced discreetly over at an oblivious K-9, and the Doctor followed her gaze. The robot dog's ear twitched. He didn't seem to understand.

"It's up to you, K-9," smirked the Doctor. "Get us out of this."

Romana could hear K-9's mechanical brain whirring. "Master?"

"You must have a flirt setting," the Doctor wondered. "Or are you permanently set on smart-arse?"

Seemingly understanding, K-9 trundled forwards, ready to deploy his canine wiles on the unsuspecting Kuricam.

"Might I say," said K-9, "that your circuitry looks particularly dazzling?"

"How dare you!" replied the Kuricam, offended. "I'll have you know that I'm a happily married camera, thank you very much. Away with you, pest!"

K-9 backed away, hanging his head.

"Don't worry, boy," said the Doctor. "You can do much better."

The Kuricam jumped up and down on the spot, demanding attention; its thin mechanical legs looked like they were going to snap under its own weight at any minute. Electricity began to spark around its lens.

"No, don't do that again!" Romana said. "We'll co-operate. What is it you want from us?"

"You must be punished. A fine must be paid, or you will be arrested."

"How much do I owe you?" asked the Doctor casually.

The Kuricam thought about this for a moment. "Sum of total infractions of the law results in a cost to the criminal of 4,650,312 Galactic Credits, and one pence."

"The penny's important, is it?"

"Vitally so, yes."

The Doctor patted himself down, knowing full well that he didn't have any money, but stalling for time while he thought of something—_anything_—that would get them out of this situation. "I'm afraid I don't have any cash on me at all. I suppose I could start a savings account with a penny and then jump forward a million years to collect on the interest, yes?"

"Unacceptable. Fine must be paid _now_."

"Oh, you jumped-up little...! Well, I can't pay, and I'm certainly not going to prison, so it seems we've reached a bit of an impasse."

"One additional option is available," said the Kuricam.

"Yes?"

"You could make a down payment of some kind, to state your intention to pay the fine in full as soon as possible. You should surrender any item of value."

"What about my companion?"

"The robot dog is almost worthless."

"I wasn't talking about K-9."

Romana punched the Doctor in the arm.

"Getting a taste for violence now, are we, Romana?"

She winked at him. He was just so _hittable_.

"Look," he said, "just take K-9. Keep him impounded until I find the money—which I will do soon—and consider it a promise that I take my standing with the law very, _very_ seriously. Deal?"

"Master?" began K-9 tentatively. "Should we not discuss this strategy first? I am not sure—"

"Proposition accepted," declared the Kuricam with a nod, which involved tilting its whole body forward to such a degree that it almost lost its balance.

Romana knelt down beside K-9, and patted him affectionately. "Don't worry," she said soothingly. "We'll be along to rescue you in no time at all."

"Thank you, Mistress," K-9 replied.

"Before you go," the Doctor said to the Kuricam, "what's so special about this painting? What's going on? Do you know who stole it?"

"Regrettably, _we_ stole it. The man depicted in the artwork is wanted for serious crimes, including unpaid bills and indecent exposure. Kuricam officers detected his likeness and made an arrest, but it seems that we were _too_ swift..."

"Yes, you were," said Romana. She suddenly remembered the security camera she had seen in the park earlier. "That was one of your lot, was it?" she asked, having explained the strange sighting.

"Correct."

"You detected the presence of a TARDIS—_our_ TARDIS—on Earth," realised the Doctor aloud. "And then you found whatever looked like the Cavalier nearby, in the art gallery. Recognising the image of him, you went in for the arrest. You put two and two together and ended up with about a million!"

The Kuricam didn't answer. Romana had previously found them intimidating, but now that she had observed their tendency to arrest _paintings_, she found them laughable more than anything else.

"And then you were just going to incinerate the painting because you got it wrong?" the Doctor went on. "This is art! It needs to be treasured and admired and loved, not burned to smithereens!" said the Doctor in what Romana observed was a curiously impassioned plea in favour of art. She never knew that he was so cultured. He was full of surprises.

The Kuricam said nothing else. It scurried over to K-9 and jumped up onto its back. The two machines disappeared in a teleport glow.

"Well," said the Doctor, "that was good. We managed to get rid of _two_ irritating machines in one go!"


	7. Chapter Seven

The Fear of All Sums

By Samuel Marks

Chapter Seven

The Cavalier hadn't known what to do with himself since discovering the radar. He wanted to do _something_, to help put the timelines back on track. But without his TARDIS, trapped in this unfamiliar world, he felt helpless. He couldn't stop a tear from breaking out, and hoped that he had managed to wipe it away before General Titus had seen it. The last thing he wanted was to appear weak.

Titus approached the corner of the tent where the Cavalier was sat, and put his arm around him. "Be strong, stranger. To die and then come back to life can't have been easy, I understand. Merely as an observer, my _own_ nerves are shaken."

The Cavalier nodded. "Cheers, pal."

"I will be here if you want to talk." General Titus wandered over to the radar and, after a few moments of studying the computer, he swore loudly.

"What is it?" asked the Cavalier, snapping himself out of his contemplation. He could feel sorry for himself later. Now, he had a problem to solve.

"We've caught sight of them." The General indicated the radar. "Hannibal of Carthage and his forces are close. They are within range."

"In range of what?"

General Titus smiled. "You will not be ignorant of the true power of the Roman Empire for much longer. Come with me."

The Cavalier followed Titus out of the tent and into the Roman encampment on the mountainside. The soldiers, too, were leaving their shelters are gathering in the centre of the camp. The Cavalier felt his hearts beating faster in his chest. Everything seemed so wrong, so terribly wrong.

A young soldier passed something to the General.

"Oh, of course!" said the Cavalier, resigned to the strangeness of this corner of the universe. "You've got a radio!"

General Titus spoke into the device. "Attention! This is your general speaking. The hordes of Hannibal have continued their advance, and have dared to defy our glorious and righteous Empire. They must be stopped! Roll out the fighters!"

"What does that mean?" asked the Cavalier. "Are you sending in gladiators to fight for you?"

"Not that sort of fighter, I'm afraid. Look to the skies!"

Right on cue, a deafening noise sliced through the thin air of the mountain, as something distant grew steadily closer. The Cavalier stared upwards, along with the Romans.

He couldn't quite believe what he saw: three sleek jet fighters zoomed across the sky, high in the clouds, leaving a trail of glorious red smoke behind them as they went. General Titus and his troops all cheered, but while the Cavalier's mouth hung open as he stared skywards, no sound came out.

There were no words.

A deep rumbling could be heard from far-off, across the Alps. It was unmistakably the noise of the jet plans of the Roman Empire dropping their bombs on the unsuspecting forces of Hannibal. But when the ground continued to shake long after the distant explosions ceased, General Titus and his forces quickly stopped cheering.

"The mountain's coming down around us!" said the Cavalier, panicked.

Though they were silent, the Romans were seemingly unconcerned.

"Do not worry yourself, stranger," said Titus simply. "There's plenty of room in the transmat pod."

One minute that Cavalier had been stood on a mountainside, with the screech of fighter planes growing terrifyingly closer by the second, and the next he was in a large stone courtyard in the middle of a city. He had finally reached Ancient Rome, but it wasn't at all like he had been expecting.

The Roman courtyard looked like it had been converted into some sort of transmat hub—ancient and modern at the same time. The stony walls were lined with electrical cables, all powering up the huge glowing circle in the middle of the floor on which the Cavalier, Titus and the rest of the Romans had appeared. The Cavalier had dozens of questions, but it seemed that he was not the only one.

A young woman hurried over to General Titus. She was holding a microphone, and was flanked by a man holding a television camera.

"A film crew," mumbled the Cavalier miserably. "Oh dear." He wondered whether the radio and the fighter jets might have been the worst of it, but it seemed that the situation was far worse than he could ever have imagined. Ancient Rome was so utterly wrong.

"General Titus!" shouted the reporter excitedly. "Do you have any comments for everyone watching at home? How was the battle? I should add, we are live, so please don't swear."

Titus flashed a winning smile, and ruffled his hair. "Do I look okay? Right. Comments? Oh, well, everything went fine. Hannibal was well and truly trounced. No problems at all. Rome is safe, as usual, etcetera."

The reporter nodded. "That's fantastic. Thank you. I'll let you and the others head off to the bath house and get cleaned up."

Not even that thought managed to put the Cavalier in a good mood. The whole situation was overwhelming. He felt so uneasy, and knew he had to act. As a Time Lord, it was his responsibility to fix it. Somehow...

But the Cavalier spotted something out the corner of his eye. Standing beneath an archway in the courtyard, cloaked in shadow, was what appeared to be some sort of black knight. Glowing red eyes looked out from behind a heavy helmet, as if piercing the Cavalier's soul.

He felt a shiver run down his spine. Somehow, in his hearts, he knew that this was the enemy who had destroyed his TARDIS. Now they were coming to finish the job—to finish _him_.

The Cavalier didn't know what to do. Should he run? Or maybe confront the strange knight? He couldn't decide. So they stood for a while, as if oblivious to the joyful chaos of the Romans all around, just staring at each other across the courtyard.

Suddenly General Titus stepped in front of the Cavalier, obscuring his view. "So, friend, what will you do know? Are you planning on staying here? I think you'll love it. We have all the mod-cons and over a thousand television channels..."

The Cavalier stopped listening and peered over General Titus' shoulder to look over at the archway, at the sinister figure beneath it. But he saw that there were now at least a dozen of the black knights, all staring right at him with those red eyes. There was no doubt about it. They were coming for him.

"S-stay here?" The Cavalier couldn't take his eyes off the figures. "Nah, General. I'm afraid I can't. Actually, I-I-I think I'd better get going. Well done on the battle and stuff." The Cavalier planted a congratulatory kiss on the General's lips, then turned on his heels and ran as fast as he could.

He hoped that wouldn't be his last kiss. Not that it wasn't a good one, but he had that privilege reserved for someone else. For an old friend from Gallifrey...

Romana waited with the TARDIS outside the art gallery, while the Doctor returned the _Laughing Cavalier_ to its rightful place. He emerged after a short while, deep in conversation with the woman who appeared to be the curator. She looked tired, and was no doubt in need of a good lie down after the dramatic theft of one of her paintings. Unfortunately for her, the Doctor was still talking.

When the Doctor had finally let the curator go, Romana asked where they were heading next. "Back to the park?" she suggested.

"Not just yet," said the Doctor. "First, we've got to see an old friend."

"Oh, yes. Poor old K-9, locked away because you can't pay your fine."

"What?" replied the Doctor, confused. "I was talking about the Cavalier! Thought we could pay him a little visit. It's been far too long since we last had a chat, and I need to warn him that some self-righteous little security cameras with a bad attitude are looking for him."

"But what about K-9?"

"Oh, he'll be okay for a while. What's the worst that could happen to him, he gets a little rusty? And I'm sure I've got a spare in the TARDIS somewhere, if it came to it."

The Doctor grinned at Romana; he was only joking. At least, that was what she told herself.

Above the entrance to the art gallery, a security camera swivelled to watch as the police box faded away. Its tiny mind clicked into action, realising that the box-shaped TARDIS might be its best hope of catching the criminal known as the Cavalier.

"Justice will be swift," it said, before it teleported away.


	8. Chapter Eight

The Fear of All Sums

By Samuel Marks

Chapter Eight

The Cavalier stopped running. He must have been miles away from the courtyard by now, and he had seen no more signs of the mysterious black knights. Perhaps he was wrong. Maybe they were statues, or... something. He couldn't think straight. His head was aching terribly.

Panting for breath, he stood leaning against a wall and tried to compose himself. He glanced around, checking that he was alone. But at the far-end of the street behind him stood one of the black knights.

"No way," sighed the Cavalier. He had to press on. "What in the name of Rassilon is wrong with this place?"

Summoning what little of his strength was left, he started running again. He turned a corner—and ran directly into someone. The Cavalier was knocked to the ground. His body collided with the tarmac painfully, and it took him a moment to regain his senses. But without looking, he knew that it was a black knight that stood looming over him.

The figure spoke in a deep, rasping voice that suited its terrifying exterior perfectly. "Nothing is wrong," he said. It was a _he_, for it was a man's voice, albeit one heavily manipulated by machinery.

"What are you talking about?" asked the Cavalier. "Of course it's wrong! There's technology here that doesn't belong in this time! It's completely impossible!"

"Incorrect," replied the black knight simply and chillingly. "It is not impossible. It is simply _improbable_. The chances are slim, yet it could still happen; indeed it _has_ happened, as you can see."

The Cavalier started to push himself up onto his feet, but the armoured man placed his heavy boot onto the Time Lord's chest, holding him down.

Unable to move, the Cavalier's voice trembled. "Who the hell are you? And what do you want with me?"

Two more identical black knights stepped out of the shadows behind the Cavalier, preventing any chances of an escape. He was trapped, and at their mercy.

"We are the Zeronaughts. And we want _you_."

The time rotor began its steady rise and fall as the TARDIS forged its way through infinity. The Doctor was busy at the controls, and once again, much to her annoyance, Romana had been reduced to simply being a passenger. She was forced to remain silent, keeping her intelligent criticisms to herself, even though she knew a faster, safer, and all-round better way to do what the Doctor was attempting.

"Done!" cried the Doctor triumphantly. "I've locked us onto the Cavalier's time signature. Wherever he is, anywhere and anywhen in the entire history of the universe, relative to our location, we can find him."

An explosion rocked the control room and it tipped on its side. The violent lurch knocked both the Doctor and Romana off their feet.

"Oh, for heaven's sake, K-9!" the Doctor said angrily, picking himself up off the floor and doing nothing to help Romana. "What have you done this time?"

"He's not here, is he? Remember? So there's only one person whose fault it is..."

"I suppose so." The Doctor thought for a moment. "Goodness, Romana, I thought you knew what you were doing!"

It took every ounce of strength in Romana's body to stop herself from answering back. Biting her tongue, she dusted herself off and checked the readings on the console. Despite the unintentional crash-landing, they had in fact seemed to arrive at the intended destination.

Outside the doors, the Cavalier awaited them.

General Titus searched long into the night to find the Cavalier, scanning all the streets of Rome, but there was no sign of him. The man was gone.

The flagship of the Zeronaught Accumulation blasted through space, slowly but surely ploughing through the inky void, past stars and planets and moons of a thousand colours. On the command deck of the starship was the leader of the Zeronaughts, known as Nil the Calculator.

He was dressed identically to the others of his faction—his whole body protected inside seemingly impenetrable black armour—and yet it was still possible to tell that he was in charge. There was something about him, the way he walked and talked and held himself, as if he simply exuded power and confidence with everything he did, subconsciously letting everyone around him know that he was dangerous.

Also, he regularly killed people, which had a similar—if not even more potent—effect.

"What is the prisoner's condition?" he asked in the low, heavy, rasping voice that he shared with all the others of his kind.

"Life signs are stable," replied a lesser Zeronaught, who was working away at a computer console nearby. "But the beat of his hearts has decreased, returning to regularity, and the lower levels of adrenaline support the conclusion that he is overcoming his fear."

"Well," said Nil, "we'll have to do something about that." He threw a lever on a nearby control console.

For a while, nothing happened. But the Zeronaughts waited patiently. A distant scream could then be heard, echoing up through the countless levels of the starship, having carried all the way from the holding cells. It was a cry of pain, as thousands of volts coursed through a body that was already weak, and that had already suffered so much at the hands of the Zeronaughts.

The Cavalier would not be able to take much more.


	9. Chapter Nine

The Fear of All Sums

By Samuel Marks

Chapter Nine

The Doctor blindly poked his left arm out of the TARDIS doors. While this looked, to Romana, to be a ridiculously pointless action, it was in fact the direct result of various complex thought processes that had occurred inside the Doctor's remarkable brain. His questionable logic wasn't immediately obvious to his companion, who watched with both amusement and irritation.

"Doctor, what _are_ you doing?"

"Checking to see if there's anything out there," he replied matter-of-factly. The exasperated look on Romana's face seemed to encourage him to elaborate. "Scanner's on the blink again, and this is the best way to see if it's safe out there. If my arm isn't sliced off or shot at, we should be okay to have a wander around."

Roman smirked. "Silly me. How could I not have guessed that's what you were doing? It's completely obvious!"

The Doctor thought for a moment. "Sarcasm?"

"Indeed," nodded Romana.

The two of them waited in silence for a few moments, and were relieved to find that nothing happened. All was well, it seemed.

"Do you want to stay here, in the TARDIS?" he asked.

"Why?" replied Romana. "Would you prefer to be alone when you reunite with the Cavalier?" She loved teasing him.

He didn't love being teased. "Certainly not! I was thinking of you, that's all. Might be dangerous."

"Oh," said Romana, "I'm coming with you. Wouldn't miss this for the world."

"Why not?"

Romana smiled. "Might be dangerous."

"Good girl," the Doctor said warmly, smiling back at her.

They shared a moment—an odd, beautiful, terrifying moment—that seemed to last for both a second and a lifetime all at once, in which the time-travellers from Gallifrey seemed to be looking right into each other's souls. Romana's hearts were beating faster than ever before, even more than when she had been running from Daleks or Mandrels or sentient security cameras. In times like these, she was reassured that beneath all the Doctor's snide comments or sarcastic putdowns, he really seemed to care about her. She wasn't sure if the same could be said about his relationship with K-9. She almost hoped not...

Out of embarrassment and unease from their meaningful glances, Romana looked away. She cast her eyes over the control console, wanting to look at something else—anything else. She was scared. She could understand the complex trans-temporal and dynamic spatial readouts of the TARDIS, but she didn't know her own hearts... Or _did_ she, she wondered, and she just couldn't admit it? Why not? Was it more that she _wouldn't_ admit it? And again: why not? There was no good reason for her silence. There was something there, between her and the Doctor, almost definitely. She cared for him, that strange, ridiculous, completely bonkers man, who was stood just a few feet away from her with his arm hanging out of a police box.

Finally, after far too long, she decided she was going to tell the Doctor how she felt—or at least how she _thought_ she felt.

She looked up again. "Doctor, I need to tell you..."

But the Doctor was gone.

Romana just caught a glimpse of his scarf trailing behind him, as the Doctor tumbled out of the TARDIS, left arm first, as if he had been pulled outside by someone—or something. Either way, it couldn't have been good.

"Doctor!" she cried, as she hurried after him.

A few minutes earlier, the Cavalier had been asleep. His mysterious captors had finally decided to stop torturing him and allow him to rest. He certainly needed it. It had been such an insane few hours, from a chase through the Time Vortex, to a trudge through the impenetrable environment of the Alps, to an encounter with not-quite-Ancient Rome. He had just drifted off and was dreaming of Gallifrey, and his old friends who had become his enemies simply because he wanted to be _different_, when he heard a noise—a familiar, beautiful, reassuring noise that woke him immediately.

The Cavalier shook off his sleepiness and sat bolt upright on the pathetic excuse for a bed, watching as a bright blue police box faded into existence. He knew it from the stories, the myths and legends on a thousand worlds right across the universe, which spoke of a mysterious and magical wanderer known only as the Doctor. Of course, the Cavalier knew his old friend by a dozen other names, but he understood why he had changed it. 'The Doctor' suited him much better. He always wanted to make people better, and from the stories the Cavalier had heard, it sounded like that was exactly what he'd been doing since leaving Gallifrey. And all those tales spoke of his police box, that rackety old TARDIS that he never fixed. The Cavalier laughed—that was very him.

But, he wondered, why had the Doctor come here? Was it random? Or had he really come looking for his old friend, the Cavalier, after all these years? He had thought that the Doctor must have forgotten him. But no, it seemed that he still thought about the Cavalier as much as he thought about the Doctor. They'd always vowed to remain friends, but then again people always did, usually right before they lost touch forever. But the Cavalier had always known that he and the Doctor shared a bond that was stronger than all of space-time. Nothing would tear them apart. But it seemed that it was more than that: now the universe had brought them together again.

He watched with bated breath for the moment when those TARDIS doors would burst open and the Doctor, in a new body all these years later, the Cavalier suspected, would look upon his old friend and smile. The Cavalier straightened the Roman armour that he still had to wear because he had nothing else, and waited to see the Doctor again.

But all that came out of the TARDIS doors was an arm—a left one, by the looks of it. The Cavalier approached it cautiously, studying it, trying to work out why it was there. Was it the Doctor's arm? Probably, he decided. Not many people were mad enough to think sticking an arm out a time machine was a good idea.

The Cavalier thought for a moment. What was he supposed to do, just stand there and stare at the disembodied arm? But what if the TARDIS dematerialised without its occupants ever leaving the ship? If that _were_ the Doctor, would the Cavalier just let himself stand there, dumbstruck, and give up the chance to see his old friend again after far too long?

"No," he decided aloud. He reached out and grabbed hold of the arm, pulling the body it was attached to out of the TARDIS and onto himself.

The two Time Lords landed in a heap on the floor.

"Hello, Doctor," said the Cavalier.

"Hello, Cavalier," said the Doctor.


	10. Chapter Ten

The Fear of All Sums

By Samuel Marks

Chapter Ten

Romana rushed out of the TARDIS just a few steps behind the Doctor, fearing for her friend's safety. Stepping out the police box, she found herself in a dark prison cell. But the environment didn't demand her attention so much as the two men lying on the floor did.

"What's going on?" she asked, in disbelief.

"Oh," said the Doctor casually, looking down at his old friend, "we were just getting reacquainted, weren't we?"

The Cavalier smiled. "It's been a long time, Doctor."

"Too long, old friend."

"Do you want to get up?" asked Romana, with her hands on her hips. She wasn't impressed.

"I suppose so," sighed the Doctor. "It's no use wasting two good legs, is it?"

The Doctor clambered up off the grubby floor, and the Cavalier did the same. He looked Romana up and down, almost suspicious of her, or at least curious. "Hello there," he said, flashing his dazzling smile. "I don't think we've met, have we? I think I'd remember you. They call me the Cavalier."

"My name is Romana," she replied formally, shaking the man's hand. "I'm a Time Lord too. I've heard a lot about you."

"All good, I assume?"

The Doctor smirked. "I left out all the naughty bits. Just mentioned how you're remembered, back on Gallifrey."

The Cavalier looked away in embarrassment. "They're not too fond of me, those stuffy old Time Lords."

"Far too serious, that lot," the Doctor said, nodding agreeably. "That's why we ran away, isn't that right, Cavalier?"

"And Romana, you've run away as well, yes?"

"Sort of," she said. "I like it out here in the universe. But I _could_ go back, one day. I've not burned all my bridges like you two did."

"Oh, I'm not _that _bad," the Doctor replied defensively. He stood tall, throwing back his shoulders and sticking his nose in the air, and said, "You, Cavalier, are in the presence of Gallifrey's Lord President!"

The Cavalier hooted with laughter. "You? No way! That's so cool!"

"I know!" the Doctor grinned, dropping his stance of mock importance. "It's a laugh, I suppose. The other day, I sent a communication cube back to the Capitol, banning all those funny hats and demanding that everyone should wear scarves like mine instead. I think they thought I was joking. I wasn't."

"Sorry about _these_ clothes, by the way," said the Cavalier, drawing attention to his Roman uniform. "They're not mine, I had to borrow them. You see, I woke up naked this morning."

Romana rolled her eyes. "Oh, you are just ridiculous—"

"Intruders!" came a heavy, rasping voice from nearby.

The three Time Lords jumped in fright, and turned to face the source of the interruption. Barely visible in the shadows outside the cell door was a Zeronaught, tall and menacing in its jet-black armour. Its piercing red eyes that shone out from beneath the helmet spooked Romana, and it felt like her blood ran cold.

"What is that thing?" she asked.

"They're the ones who kidnapped me," said the Cavalier. "Well, they _have_ kidnapped me. _Present_ tense. I'm not free yet. Yes, that's a point. Doctor, why haven't we left already?"

"I don't know," the Doctor shrugged. "I don't even know where we are. Some sort of spaceship, I assume?"

"At the heart of the Accumulation's fleet, escorting the prisoner to our home world," said the Zeronaught. "We are the Zeronaughts, and we will destroy you."

The cell door swung open, and the Zeronaught stepped through. It raised a gloved hand that sparked with fiery red energy as it advanced upon the Time Lords.

"Stay back, you two," said the Cavalier confidently. "I'll handle this." He raised his own fist, which also began to glow brightly. Golden energy played around his hand, lighting up the darkness and cutting a trail through the air as he swung it towards the Zeronaught.

The knight in black armour staggered backwards, shaken by the blow, until it tumbled onto the floor of the cell.

"Knocked him out cold!" the Doctor observed admiringly. "Nice work, Cavalier. How did you do that?"

"Used my residual regeneration energy to give it an extra kick. Well, an extra _punch_. But you know what I mean."

"You've recently regenerated, then?" asked the Doctor. "Congratulations!"

"Not exactly," said the Cavalier miserably. "It was my twelfth one. This is my thirteenth and final body." He looked himself up and down. "I know, I'm not exactly going out on a high, am I?"

"Oh, I wouldn't say that," said the Doctor, looking his old friend up and down. "I like it. I think it suits you."

By this point, Romana's eyes had been rolling almost constantly, so much so that her head started to ache. "Doctor, we've got to go," she urged.. "There must be more of those things."

"We're okay for a while," said the Doctor, kneeling down beside the unconscious figure. "Before we leave I have to find out some more about this lot."

"Yes, what are these so-called Zeronaughts?" asked Romana. "Are they like astronauts?"

"Not really. They're explorers of the worlds of physics and mathematics, not the wonders of the universe. To them, reality has no beauty; it is merely a string of numbers. They see the great questions about life, the universe and everything not as enjoyable philosophical debates but as equations that need to be solved. That's their aim. That's what they do. They take the fun out of everything, balancing the problems of reality, reducing everything to zero."

"So why did they kidnap him?" Romana asked, gesturing towards the Cavalier.

"Good question," mused the Doctor.

"Oh, never mind that," said the Cavalier, with a dismissive wave of his hand. "I'm always getting kidnapped, it's nothing really. It's become a bit of a hobby, I suppose. A better question would be: why are they in these big scary suits?"

"Because it makes them look big and scary," said the Doctor simply. "They're only scientists, remember. And pompous brainboxes like the Zeronaughts frequently get picked on anyway. Imagine how many more people are going to picking on them when they tell them that they're trying to alter the fabric of reality. The suit is protection, keeping them alive."

The Doctor bent down over the body of the unconscious Zeronaught, and carefully removed its helmet. Beneath the protective mask was the face of an old man, withered and tired and wrinkled with age. He was still breathing, just about.

"He looks old," noted Romana.

"Yes," the Doctor replied, "but he's even older than he looks."

He reached into his pockets, rummaging around, searching for something. He seemed to come across several items that he didn't need, and casually passed them over to Romana and the Cavalier respectively, so he could keep looking. After apparently finding everything except what he was looking for—including a pocket watch, a whistle, and a half-eaten apple, which his companions were left holding—the Doctor eventually found his sonic screwdriver.

"The armour is infused with nanogene technology, preserving the body within indefinitely. This suit has been programmed to slow down the aging process, to keep the body alive for as long as possible with bio-enhancements." The Doctor was scanning the unconscious Zeronaught with his trusty gadget. "They're more machine now than man. They're basically immortal. The Zeronaughts can live for ever!"

"And that's bad, is it?" Romana asked.

The Doctor nodded.

"I can't help but think," said the Cavalier, "that for us—three Time Lords—to say that is perhaps just a _bit_ hypocritical..."

"You mentioned altering the fabric of reality," said Romana. "Is that what they're trying to do?"

A dark expression fell across the Doctor's face. "Like any mad scientists, observing the world isn't enough. They've got to use their genius to change it, to manipulate it. There must be a secret—a machine or ability of some kind—that allows the Zeronaughts to rearrange the building blocks of the universe. Given the time, and the solution to the equations, they can do anything!"

"And you've never thought about _stopping_ them?" asked the Cavalier, confused. "I've heard all these legends of the magnificent Doctor, who saves the universe time and time again, yet you know all of this and allow it to go on?"

"They're an incredibly secretive community. I don't know, maybe they're shy. But I've only heard rumours, read eyewitness accounts of people who think they glimpsed a Zeronaught in the darkness. No one truly believes they exist. I'm the only one foolish enough, and it turns out I was right! Oh, that's a nice feeling."

"Yes, reality is in serious danger," Romana said sarcastically. "How wonderful that feels!"

"I got the sarcasm that time, and I've also got the Zeronaughts' data now," said the Doctor, drawing their attention to the sonic screwdriver. "With it, I can find their planet and take them by surprise. This ship will be too well defended for a direct assault, and we'd stand no chance against the whole Accumulation at once. The element of surprise is always good."

The Doctor turned on his heels to retreat back into the safety of the TARDIS, but he quickly realised that the element of surprise was only good when you weren't on the receiving end of it. The harsh light of a teleport glow illuminated a darkness of the cell, and the familiarly ridiculous sight of a Kuricam appeared.

"Oh, not you again!" cried Romana.

"What are _those_ things?" asked the Cavalier.

"They're silly," said the Doctor. "They're self-important, bureaucratic, jumped-up little machines. And they're looking for _you_, Cavalier."

"Me? Why?"

The Kuricam took a few unsteady steps forward on its thin metal legs. "Crimes are too numerous to list. Battery life would not last long enough to recount them all."

The Doctor laughed. "And they run by battery, too! They really are absurd. The future of policing, eh? What a joke—"

But the moment was interrupted by a hum of power, as the Zeronaught began to wake up. And when it did, it wouldn't be happy to see the prisoner escaping.

"Look," said the Doctor to the Kuricam, "we're in a bit of a rush, so if you could just let us go that would be great."

The Kuricam sparked with electricity, as it powered up its small but powerful weapons systems and prepared to fire, in an attempt to threaten the Time Lords. "Proposition rejected. The renegade known as the Cavalier has finally been located. He will now be apprehended. Justice will be swift."

"Oh, you're a real nuisance, you lot," said the Doctor. "So is this our choice? Stay here, arguing with you, and get caught by the Zeronaughts? Or hand over the Cavalier, when I've only just found him again after all these years, and get away scot free?"

The Kuricam seemed to think about this for a moment. Even its advanced circuitry struggled to keep up with the Doctor's fast mind and faster mouth. "Correct," it decided, finally.

"Hey, it's fine," said the Cavalier. "I'll go quietly. I don't mind moving from one cell to another. It must just be one of those days. But I hope you're better at hospitality than these Zeronaughts."

"You will be taken to the Visendi Detention Complex. Your fellow inmates handle hospitality," announced the Kuricam grimly.

The Cavalier looked worried. "Doctor, before I go—before this thing takes me away—I have to tell you something. I don't know if it's connected to the Zeronaughts... It might just be coincidence, or totally unconnected, I don't know... But something is wrong. Something has happened to Time itself."

"Something bad?" "Something very, _very_ bad. Ancient Rome is not so ancient any more. The real problem might be bigger than that, and Rome could be just a symptom of the illness, but it's a good place to start. I have the strangest feeling that the whole universe might be in very great danger. Solve this, Doctor. If anyone can, it's you. When I get out of jail, I want a universe to come back to."

The Doctor smiled reassuringly. "And I'll be waiting for you, too."

The Cavalier winked, and he and the Kuricam disappeared in a teleport glow.


	11. Chapter Eleven

The Fear of All Sums

By Samuel Marks

Chapter Eleven

Far across the universe, the Zeronaughts worked in secret. The planet where they had made their home went unnoticed by most space tourists. Their world was sandwiched between Planet of the Coffee Shops and Planet of the Shopping Malls, ensuring that nobody paid the slightest bit of attention to Planet of the Slightly Odd Physicists.

On the surface of the world that was hidden in plain sight, the Zeronaughts' top-secret fortress was tucked away. Inside, they worked tirelessly, day and night, to solve the questions of the universe. It was a mammoth task, a mighty undertaking, unimaginable in its scope and highly admirable in its ambition. Finding the solutions to these problems was universally acknowledged to be completely impossible.

But the Zeronaughts refused to accept that: they simply didn't do impossible.

With Nil the Calculator in charge of the Zeronaughts' fleet, he had been forced to leave Zilch the Abacus in charge. It was a decision that both of them regretted almost immediately.

Zilch stood in the command centre of the Zeronaughts' fortress, monitoring the computer screen that displayed the myriad rooms and the countless Zeronaughts within them. He oversaw the Zeronaughts celebrating at the end of a successful day solving the problems of the universe. Zilch had used his new level of authority to propose they all throw a massive party and dance the night away. But the other physicists had not been so keen. For the Zeronaughts, a 'party' meant time spent doing slightly less challenging sums than normal, just for fun.

A _bleep-bleep-bleep_ from the computer indicated an incoming message, and Nil the Calculator appeared on a video screen.

"Oh, hi," said Zilch. "How did the kidnapping thing go?"

"We found the Cavalier, but then he got away," hissed Nil angrily.

"Bad luck," Zilch said. "Was it the Doctor? Did he mess up our plans like we expected?"

Nil nodded. "Curse him!"

"Hey, calm down. We'll get him eventually. Don't worry about it. Just chill out, okay? Is he coming here? The Doctor?"

"If all goes to plan, yes," said Nil. "The fleet will be back in orbit shortly. We will ensure everything is prepared for the Doctor's arrival."

"Should I get some of the guys to organise a nice spread, then? With snacks and nibbles and some of those cupcakes with the little sprinkles on? What are they called, hundreds and thousands? That's numbers-related, isn't it? Seems very apt, I think. The Doctor might appreciate that."

Nil gave an impatient sigh. "Just leave everything to me. This is the most important day in our lives, Zilch. Everything the Accumulation has been working towards has led to the moment that is now on the horizon. Nothing can go wrong. Do you know what day it is, my friend?"

Zilch thought for a moment. "Friday?"

"No. That's not what I meant. And anyway, it's _Thursday_, you fool."

Zilch sighed heavily. "What, really? I thought I had a day off tomorrow. I've made plans and everything. I'll have to cancel my tickets to _Chitty Chitty Bang_—"

"Silence!' barked Nil. "You misunderstand me, Zilch. Today is no ordinary day. Today is the day the Doctor falls!" He began to laugh manically, throwing his head back, seemingly physically excited by the idea of murdering the Time Lord.

Zilch looked around awkwardly, wondering if perhaps he should join in.

He didn't.

The time rotor rose and fell hypnotically, as the TARDIS danced across the dimensions. The Doctor and Romana were working frantically at the controls.

"This must be why K-9 changed," Romana thought aloud. "These Zeronaughts must've been behind it. What else have they been up to?"

"Let's find out," replied the Doctor, as he flicked a switch on the console. "I'm getting massive readings from Ancient Rome, just like the Cavalier said. Somehow, the Romans have got their hands on technology that is, for them, futuristic."

Romana studied a screen closer. "Did you see this? In 218 BC, there are aeroplanes in the sky, cars on the road, submarines underwater... There are reports here saying that the Empire is stretching out across the world at an incredible rate. This is impossible!"

The Doctor's eyes were even wider than usual, as if he'd just had a sudden thought. "That's it," he said cryptically. "Romana, as ever, you've cracked it, because as unlikely as this is, it's certainly not impossible. It's just _improbable._ The Zeronaughts must be behind it, but how? _Why_?"

"Is it just Ancient Rome?" asked Romana. "Or are they corrupting other points in space-time, too?"

The Doctor immediately returned to the controls, flicking switches expertly. Romana stood back and let him continue alone. He knew his ship better than anyone else ever would. They worked together, in sync, more than any other pairing in the universe. She had forced herself to accept that long ago.

"I've got another trace," said the Doctor. "Oh, this is unbelievable. There are mobile phones in Ancient Egypt!"

"Oh my..." Romana didn't like this at all.

"No, no, no! I'm losing the signal. I'll try to follow it through Time, see if I can pick it up again at a later point. Hold on..." The Doctor reached under the console and found the TARDIS telephone. He dialled the number that was displayed on the screen. After a while, someone seemed to answer.

"Hello?" said the Doctor into the phone. "Who's this?" His brow furrowed. "It doesn't matter how I got this number, you'd never understand. Is Cleopatra there by any chance? Can I speak to her? We're old friends. Tell her it's the Doctor. Hello?Can you hear me? Hello!"

Frustrated, the Doctor hung up the phone. "Lost the signal," he said. "But at least we've learned that it's not just Ancient Rome. What else have you found?"

Romana was at the computer screen, scanning all of space-time for more anomalies. Her hearts skipped a beat every time she found further evidence that the universe was breaking down. There were countless corruptions in the timelines: spaceships launching from the 18th Century, explorers settling the New World with clones, cyborgs in the Middle Ages... This was bigger than she had suspected.

"Romana, focus!" cried the Doctor, snapping her out of her worried trance. "Don't panic. Just talk to me. What have you found?"

"Yes, sorry," she replied. "Well, there are reports right across the universe, all rippling out of that one original corruption in Ancient Rome, like when you drop a stone in the water. We have to stop this, Doctor!"

"I know!" he bellowed, angry with himself more than anyone else. He was visibly struggling to think of a solution. "Look." He sighed. "We'll just have to go to the Zeronaughts' planet and confront them. It's dangerous and stupid, yes... But it's the only plan I've got."

"We have to do this," said Romana simply. "The universe is in danger, and we have to save it."

The Doctor looked up at her, his worried expression falling away and becoming something warmer and more familiar, and if you were a Zeronaught, infinitely scarier.

The Doctor was smiling.


	12. Chapter Twelve

The Fear of All Sums

By Samuel Marks

Chapter Twelve

The Cavalier sat down on the bench of the prison cell. He let out a great sigh. He had to spend the next three-hundred years in this tiny room—only two-hundred if he was well behaved, but he knew that he wouldn't be—and worst of all, he had the spend all that time in a body that he didn't like. He was disappointed with his latest—and last—regeneration. He wanted to go out on a high, as some Adonis-like figure who could strut around and flex his muscles at random strangers without them becoming afraid, only impressed. Instead, he was stuck looking like a Maths teacher in a Roman fancy dress costume, and that was destined to be his appearance until the end of his days. The Cavalier would have to be careful, take no risks, stay out of any unnecessary danger.

He sighed again, thinking about the boring future that lay ahead of him. He was tired of this body already. Under his breath, he cursed the Time Lords and their silly old rules.

With a few centuries of solitary confinement ahead of him, the Cavalier searched through his pockets to see what he had in his possession to pass the time. Confident in the security features of the Visendi Detention Complex, the Kuricams had not taken the time to search the Cavalier at all. Or perhaps pride was only one explanation: it was more than a little tricky to conduct a full body search on prisoners when you didn't have any arms.

The Cavalier found his Micro-Matrix: a Time Lord device that allowed him remote access to the archives of Gallifrey. It was about the same size as a mobile phone, but could do so much more. In an instant, the Cavalier could bring up the entire records of the Sontaran/Rutan War, and learn the exact number of causalities down to the nearest half-batch of troops. Or he could track the timeline of any being in the universe, down to the tiniest details: he could pick a person, and discover the brand of toothpaste that they used on any given morning. In short, the Cavalier had in his possession a device that could tell him almost anything about everything that ever happened or ever would happen.

Instead, he watched cartoons.

As much as the Cavalier was enjoying the exploits of a pixelated boy and his talking goldfish, he was too distracted to truly pay attention to it. He was too occupied with recent events to think about anything else. The enigma of the Zeronaughts puzzled him, with their mysterious and sinister belief that nothing was impossible. Could that possibly be true, or would the Doctor expose them as frauds? The Cavalier tried to think of any other explanation for the improbability of Ancient Rome discovering the secrets of advanced technology way ahead of their time, but couldn't. He shuddered at the thought of the Zeronaughts' power.

Making further use of his Micro-Matrix, he checked the records of Ancient Rome. The screen flickered, and then the device turned itself off. Confused, the Cavalier tried again. There was still nothing, like the data couldn't be accessed. He found himself wondering if it the device was broken, but he knew that it wasn't; it was one of the most sophisticated pieces of technology in the universe. So if the Micro-Matric wasn't at fault, then the records themselves were. The data had been corrupted, just like Ancient Rome itself. History was falling apart, and the Doctor was trying to repair it all on his own. The Cavalier refused to sit back and do nothing. He had to get back to his old friend and help in whatever way he could, but he was locked up and stuck in the cell.

He needed to think of a way out. Frustrated, he tucked the Micro-Matrix back in his pocket, and as he did so, he felt something else in there—something strange that he hadn't been expecting. He pulled it out and looked at it. It was a small, cylindrical device that the Cavalier didn't remember acquiring: it was a whistle.

The Cavalier eventually remembered the Doctor emptying his pockets in the frantic search for the sonic screwdriver, and handing various other items in his possession to his fellow Time Lord. In the confusion, the Cavalier must have pocketed the whistle absent-mindedly. With nothing else to occupy his time, he shrugged his shoulders and blew into the whistle. He was disappointed to find that it made no sound. He tried it again. Still nothing.

At that moment, much to the Cavalier's surprise, the back wall of the prison cell exploded, showering him with dust that swirled around the cramped space, pouring into his eyes and lungs. He coughed and spluttered, and tried to see again.

The Cavalier's vision began to clear, and he looked up. He saw, trundling out of the chaos, a small robotic dog. Smoke was still trickling out of the machine's recently fired gun, which quickly retracted back into its head. His ears twitched nervously. "You called, Master?" he asked.

The Cavalier looked at the dog, then at the whistle—the _dog_ whistle, he realised—and broke out into a huge grin. "Oh," he said, surprised and delighted all at once. "That was handy."

"You are not the Doctor-Master. Appearance correlates with that of the rogue Time Lord known as the Cavalier."

"My reputation precedes me, I suppose. Thanks for the rescue."

"I am K-9. I am at your service."

8"We need to get out of here," said the Cavalier, "and return to the Doctor. He needs my help, I'm sure of it. I can't let him face this on his own."

K-9 began to wag his tail excitedly at the mention of his master's name. "Affirmative! I can manipulate the residual teleport energy that remains from the Kuricam's presence." There was a hint of pride in his voice, like he had been waiting for a moment to be the hero for far too long. "We can make one single trip across Time and Space. Would you like me to lock onto the Doctor-Master's location?"

"Do it, K-9!" cried the Cavalier.

A great whirring noise filled the air, as K-9 began to shake violently, glowing with a bright light. One moment he and the Cavalier were in the cell, and the next they had blinked out of existence.

A few seconds later, Camera 3-7-9, in charge of monitoring the condition of Prisoner Number One of Great Important Who Must Never Ever Be Allowed To Escape Under Any Circumstances Whatsoever, returned from its tea break. It scanned the cell and found, much to its surprise and horror, that the one they called the Cavalier was gone. Thinking fast, it raised the alarm, but then suddenly realised that it would quite rightly be blamed. Its love of tea and biscuits would be its undoing, as it was always going to be.

So Camera 3-7-9 disappeared, to take early retirement.

The lamp atop the TARDIS lit up the darkness, as the police box faded into existence. The Doctor stepped out, followed by Romana. He reached into his pocket and retrieved two torches, one of which he threw to his companion. The beams of light sliced through the heavy blackness, though there was little of interest to see.

"What is this place?" asked Romana. It made her feel uneasy, and chilled her to her very core.

"We're on the Zeronaughts' home world, in what appears to be a temple or fortress of some kind," the Doctor replied. "The heart of their empire. They built this place to work in secret, so the stories say. No one could find them here, or even suspect what they were doing. All this time, they were working to destabilise the universe. I only hope that we haven't left it too late."

Noticing his sadness, Romana took hold of his hand. "We can do this, Doctor," she said warmly. "Don't give up, not yet. First, we do our best to fix it."

The Doctor nodded. "Let's have a look around."

Their footsteps echoed around the stony halls of what appeared to be a crypt. The two of them climbed a staircase, of which one of steps crumbled beneath the Doctor's weight. Romana held him steady, and together they continued on.

In the darkness, the torchlight reflected off something shiny. The Doctor and Romana froze, spooked. Looking closer, they realised they were looking at a suit of armour, exactly as the Zeronaught they had previously encountered had wore, though this one was still, immobile. It was stood upright in a space in the rocky wall.

The Doctor cautiously approached it, urging Romana to stay back. He looked into the suit's dead eyes, and seemed relieved to get not reaction. He tapped the armour and observed the hollow sound. Waving the sonic screwdriver over it, he broke into a smile.

"Diagnosis?" Romana asked.

"Defunct," the Doctor declared. "Out of action. Put aside for repairs, perhaps? Or waiting for a new occupant? Not sure, but either way it's no threat to us."

"Good," said Romana. "That's very good. _Extremely_ really very good."

"Why?"

The Doctor turned as Romana shone her torch around the rest of the chamber. At least a dozen other suits—maybe more—lined the room. They were in a similar state to the one the Doctor had examined. He began to pace around the room, examining each of them in turn. Romana stood back, watching him.

"This is fascinating!" he said. "Oh, I could get some marvellous data from these, maybe even work out their Achilles' Heel..."

"Nice man, Achilles," said Romana.

The Doctor screwed his face up in disagreement. "A bit fictional for my liking."

Romana smirked at him. "Says the man who's friends with Sherlock Holmes."

"That's different!" cried the Doctor defensively. He thought for a moment. "I'm not sure _why_, but it probably is..." The Doctor patted himself, but seemingly couldn't find what he needed. "Romana, could you fetch me some equipment from the TARDIS? I'll need to run some tests on these suits here."

Romana nodded agreeably: anything, however slight or trivial, was better than staying in this crypt, surrounded by a dozen jet-black suits of armour. "What do you need?"

"The blue doo-dad, and the light-up flashing thingymajig."

His companion sighed. "Don't get too technical, will you, Doctor?" Regardless, she headed off. It worried her slightly that she knew exactly what the Doctor was referring to. He was having a terribly detrimental effect on her thorough and lengthy education, she thought, as she wandered back to the TARDIS.

But it wasn't there.

Romana froze. "It's gone?" she muttered under her breath, unable to believe it. She opened her mouth to call up to the Doctor, but a panicked outcry, which she recognised as coming from him, interrupted her.

Turning on her heels, Romana ran to his aid. But in her haste, she forgot about the broken step. She tripped and landed flat on her face. Shaken, she tried to focus as she thought she heard footsteps, though she couldn't be certain. Her head was spinning, and she couldn't see straight. Sensing someone stood over her, she looked up and her vision began to clear.

Two Zeronaughts were restraining the Doctor, holding him tightly. Unable to move, he gave a weak smile as he looked down at Romana.

Another two of the walking suits of armour appeared behind her, hauling Romana to her feet. "You said they were broken!" she cried, noticing that all the suits were very much _not_ broken.

"They were. This whole thing—them coming back to life—is completely impossible..." The Doctor trailed off, thinking hard. "No. Oh, of _course_ not. To these guys, nothing is impossible. Just improbable."

The Zeronaughts led the Doctor and Romana into the darkness, into the unknown.


	13. Chapter Thirteen

The Fear of All Sums

By Samuel Marks

Chapter Thirteen

The Doctor and Romana were forcefully escorted into a huge chamber, the walls of which were lined with computer terminals, displaying seemingly endless strings of numbers and complicated equations—they were so difficult to understand, in fact, that it took Romana a few more seconds than usual to solve them. Zeronaughts were sat at each terminal, staring intently at their own personal screens, typing rapidly on their computer keyboards.

"Welcome to our home, time-travellers," began the Zeronaught that stood at the head of the crowd. He looked to be the one in charge. "I am Nil the Calculator.

"And I'm Zilch," said a second Zeronaught brightly. "Hello!"

"Not now," hissed Nil. He cleared his throat. "Tell me, Doctor, what do you think of our base of operations?"

"Impressive," said the Doctor admiringly. Romana noted that his appreciation seemed genuine, and not like the false niceties that he displayed to most of the evil geniuses that they encountered on their travels.

"No doubt you've heard the legends of our people," said Nil the Calculator, standing face to face with his restrained prisoners. "How do we measure up against the stories? Do we exceed your expectations?"

"Almost," the Doctor replied, gazing around casually, "but I was expecting some sort of welcome party, and a few nibbles wouldn't have gone amiss. I do love those little cupcakes with sprinkles on."

Zilch leaned in close to his boss. "I told you," he whispered.

Nil waved his hand dismissively. "You can see, Doctor, how we work to solve the greatest problems in the universe. Assigning everything a numerical value, transforming all of creation into equations, we can reach the answers that philosophers have bickered over for centuries. We laugh at men like Aristotle and Descartes!"

"So did we," said Romana, "but then again, they were incredibly witty."

"Let me show you, Time Lords, something that will _really_ impress you..."

The Zeronaughts that held the Doctor and Romana firmly by the shoulders forced them to the centre of the chamber, where a mighty machine was brought to their attention. Wires and cables connected the base of the device to every computer bank in the room, and atop the machine was an enormous lever.

"That's a big one," said the Doctor, "isn't it, Romana?"

"Huge," the Time Lady agreed. "What does it do?"

Nil gave a deep, booming laugh from within his suit. "Everything."

"Don't be _too _specific, will you?"

"It's true, though. This is the heart of the Zeronaught Accumulation. It can do anything and everything—whatever we want it to. It can achieve the impossible."

"Yes, we noticed," said the Doctor. "Guns in Ancient Rome, and similar effects right across the universe, all echoing out of that original corruption in Time. Do you have any idea what you've done?"

"Indeed," replied Nil, "but the question is, Doctor, do you have any idea _how_ we did it?"

The Doctor screwed his face up, as he thought hard. "Of course I do. But, umm, while don't you tell me, just to be sure, and I can check if I was right?"

"We, the Zeronaughts, are the greatest minds in the universe. Expert physicists. Skilled mathematicians. All-round brainboxes. We can work out, for instance, the probability of anything happening. What are the chances of advanced technology being developed in Rome? Only we know. But what, you may ask, is the use of that information? That is why we created the machine you see before you. We feed the numbers into this marvellous invention, and the code is transmitted across all of Time and Space."

"You'd need to unravel the base code of the universe or solve the Skasis Paradigm in order to do that!" cried Romana, horrified.

"Oh, we figured out those simple sums ages ago," said Nil. "Didn't we mention? We're _very_ good."

"Why?" asked the Doctor. Romana noted a dark look fall across his face.

"Because we're really clever—"

"No. _No_. Why do you want to change the universe in this way? What do you get from it, eh? Is it all just a bit of fun to you?"

Nil sighed, the sound echoing out of his suit like a terrible winter's breeze blowing through the chamber. Romana shivered.

"We _know_ everything," Nil said. "Nothing is a mystery to us any more. The Zeronaught Accumulation has achieved its aims. Our pursuit of knowledge has ended. Now we desire a new universe, one infinitely stranger than this one, with new problems to solve! "

"So you don't care what happens to this one?" asked the Doctor. "You don't think about the consequences of your experiments? How selfish! I happen to be rather fond of this particular reality, thank you very much. But if you're as powerful as you say, and you want to bring about an end to this universe, why haven't you done it already? I mean, I'm not complaining or anything..."

"There is, reluctantly, one thing standing in our way. In our world, nothing is impossible. We could make anything happen. We brought peace to the war-torn world of Zarathstra! We gave single-celled organisms the means to develop faster than light travel! We even got the human known by all as Weird Steve a girlfriend of reasonable attractiveness! But we encountered a problem. In our search for the likelihood of this universe suddenly ending, and a new one taking its place, we found something we never suspected. A reading on our computers that we never dreamed existed."

"What was it?"

"Such a thing was, apparently, genuinely _impossible_."

"Why is it impossible for the universe to cease to exist?" asked the Doctor.

"Because of _you_," hissed Nil. "You, Doctor, are the saviour of worlds, the bringer of peace, the harbinger of joy and prosperity. Records indicate that you would never, ever allow the universe that you adore—and that adores you in return—to be destroyed."

A huge grin broke out across the Doctor's face. "Well, I'm flattered. It's always nice to get some positive feedback, isn't it?"

Romana began to work everything out in her head. "So," she deduced aloud, "that's why we're here. You needed to get the Doctor here, to your home, in order to kill him. If you remove him from the equation—literally, in this case—then your plan can advance. That's why you kidnapped the Cavalier, to get our attention, to put us on your trail. You lured us here, and we've ended up right in the middle of your trap."

"And that is also why we reached out and changed your beloved dog," the Zeronaught went on. "But you seemed relatively unconcerned by that, so we turned our attention to your old friend instead."

"If you wanted me," said the Doctor, "you should've kidnapped Romana instead. I'd have dropped everything to come and rescue her in a heartbeat."

Despite everything, Romana felt a smile breaking out. "Doctor, I'm touched, really..."

"I mean, she's got a TARDIS key. Can't have that falling into the wrong hands."

Romana tried to wrestle free from her captors in order to give the Doctor the great whack on the arm that he deserved. "You _have_ to go and ruin it, don't you?"

The Doctor shrugged, oblivious, as the Zeronaughts held his companion back.

"You are complicated, Doctor, I'll give you that," said Nil, who took to pacing around the chamber.

"Oh, you sound just like my therapist!" said the Doctor, keeping his steely gaze fixed upon the Zeronaught leader. "I told him, time and time again, I said, Sigmund, don't keep overanalysing my dreams. The Time Vortex isn't _at all_ symbolic, I tried to reassure him, but he wouldn't listen. You see, in Freudian analysis, a tunnel like that would represent a—"

"Are you capable of being silent for a moment?" asked an exasperated Nil.

"I have no idea. I've never really tried."

"What I meant was, you are a complicated event in space-time, immune to the effects of our machine. So are your companions and your TARDIS. That's why we couldn't affect you directly, rather annoyingly for us. Is there anything you can't do?"

"I'm terrible at making desserts," he admitted. "My meringues, in particular, are frankly a bit rubbish. But I really don't think it's worth killing me over that, do you?

"There is another option, Time Lord and Time Lady," Nil went on tantalisingly. Romana could feel his cold breath against the back of her neck as he paced around her.

"We're listening," Romana said, shivering.

"There is no denying that your minds are great. We observed what you accomplished in primitive Paris, with remarkable Time experiments. Not to mention that business on Earth, in the dwelling known as Cambridge." He paused, taking a deep, mechanical breath. "Join us. Become a part of the Zeronaught Accumulation. Wear our armour with pride! You will live for ever!"

"And you get a free pen, too," added Zilch, holding up a cheap biro.

"Consider our offer," Nil urged. "You do not have to die. You must simply agree not to stand in our way."

The Doctor laughed. "I'll never join you."

Romana nodded in agreement. She and the Doctor stood firm, together. Until the end.

"Then I'm afraid, children of Gallifrey, you must die." Nil raised his mechanical hand, which began to glow with fiery energy. Romana could feel its warm glow across her face as he moved it towards her, ready to end her life. "You will stand and watch, Doctor, helpless to prevent the death of your closest friend. Before your own end, your hearts must break." The Zeronaught broke into a terrible laugh.

Romana looked over at the Doctor, for what she supposed would be the very last time. She hoped that he would speak what was in his hearts, though she knew that she couldn't bring herself to say how she truly felt either.

They would die never knowing, she reasoned sadly, if the other felt the same way. But then she allowed herself a smile: no, they both knew.

Romana closed her eyes. She waited for death to come.

Instead, the TARDIS came.


	14. Chapter Fourteen

The Fear of All Sums

By Samuel Marks

Chapter Fourteen

The lamp atop of the police box glowed brighter than ever before, flashing with pure white-hot intensity as the TARDIS faded into existence nearby. The Zeronaughts restraining the Doctor and Romana released the prisoners from their grip in order to shield their eyes.

"W-what?" muttered Nil, his concentration broken; the light around his hand dissipated.

"_What_?" Romana said, allowing herself to open her eyes again to gaze upon the wondrous sight.

"_WHAT_?" cried the Doctor. His eyes were wide.

For the first time, even the Zeronaughts at their workstations looked around, amazed at the situation. No one could quite believe it.

"This is impossible!" Nil said.

The TARDIS doors creaked open, and a man stepped out, backlit by a magical white light, causing him to become little more than a powerful, intimidating silhouette.

"Impossible?" repeated the man. "Nah! Like you lot keep going on about, nothing's impossible." The man stepped forward, into the chamber.

"Just _improbable_," finished the man—the Cavalier.

Romana looked over at the Doctor, who seemed so delighted. This time she wasn't at all jealous, because she was just as happy to see their new friend.

K-9 followed behind a few moments later, the TARDIS doors swinging shut as he rolled over the threshold.

"Cavalier!" cried the Doctor, grinning. The Zeronaughts held him back, stopping him from running over to his old friend, which he clearly desperately wanted to do. "You're here! Romana, look—it's the Cavalier!"

"And me, Master," added K-9 feebly.

"What?" The Doctor only just seemed to notice the dog. "Oh. Yes. Hi there, K-9."

"You stole the TARDIS!" wondered Romana aloud, looking over at the Cavalier. "Why? Where did you go? Do you have a plan?"

"Bit of a plan," mumbled the Cavalier. "But you might not like it."

"Why? What have you done?"

In an instant, Romana worked it out and, judging by the worried look on the Doctor's face, he had too.

"Oh, you haven't done _that_, have you?" the Doctor asked.

The Cavalier nodded nervously.

"It's risky," Romana said when the Cavalier looked away, perhaps worried that he had made the wrong decision, "but it just might work."

Nil and the other Zeronaughts looked between them, completely baffled. "Will someone _please_ explain to me what you are talking about?"

The Doctor clapped his hands together decisively, taking control of the situation. "Okay, listen up, you lot," he said to the Zeronaughts. He strode confidently around the room, staring at each and every one of the black-clad knights, and all they could do was wait to see what he would do. His manner, his confidence—it scared them. They couldn't begin to guess what he was planning, but they guessed that it wouldn't be good. They were right.

"You think you're making progress," the Doctor continued, "but it's all so derivative, reducing everything to zero, thinking only in numbers. What must that be like? Hell, I think. You see reality merely as strings of numbers, statistics, rather than what it actually is. And the universe is beautiful without you messing with it, you improbable astronauts. But you just can't help but interfere, can you? Take Ancient Rome, for instance. A magnificent civilisation, remembered for centuries for all the right reasons. And then you went and changed everything about it, advancing them, giving them superior technology. Which, of course, just meant that they only created bigger and more powerful _guns_. Now I reckon, as you see everything as numbers, you've forgotten what guns can do, haven't you? Well, let me jog your memories." The Doctor flashed a manic smile. "Guns can do _this_."

At that moment, everything went to hell. The roof of the Zeronaughts' temple was destroyed in one almighty blast. Romana, the Cavalier, K-9 and the Zeronaughts all looked up, in awe. A dozen jet fighters streaked across the sky, leaving a trail of smoke behind them. The Doctor, however, kept his steely gave firmly fixed on Nil the Calculator. His smile had fallen away and Romana thought that the Time Lord had never looked more serious.

A chunk of rubble tumbled downwards, landing on top of the Zeronaughts' precious device in the centre of the room. Sparks exploded out of it, and it made a whining, straining noise.

"The universe that you corrupted," the Doctor said, demanding Nil's attention as he mourned his device, "is fighting back to destroy you. They realised what you did, how you changed them, and they weren't happy about it at all. The Zeronaught Accumulation is a plague upon reality. A virus, a disease! But I've got the cure. Well, of course I have...

"I'm the Doctor!"

There was another explosion nearby, and this time one of the walls of the temple was blown inwards. A dozen Roman soldiers strode in through the smoke, let by General Titus. On his shoulder stood a single Kuricam, like a pirate and his parrot.

Titus drew his sword and held it at the Doctor's throat. "You are scum," sneered the general, "and you will be annihilated."

"No, no," said the Cavalier nervously. "Not him. The ones in the mechanical armour—_they're_ the bad guys."

Titus cleared his throat. "Sorry, sir." He swung his sword away from the Doctor, and instead aimed it at Nil. "You are scum," he repeated, "and you will be annihilated."

"You are under arrest for temporal disturbances," said the Kuricam. "Justice will be swift."

"Do you surrender?" asked the Doctor. "I would if I were you."

Nil thought about this for a moment. Then, deciding, he cried, "Never!"

His hand glowed with blood-red energy, and he swiped at General Titus. The Roman blocked with his sword, and steel clanged against steel. The two of them were locked in battle: Nil was forcing his hand down upon Titus while he held him off with his sword braced against the Zeronaught's forearm.

Nil gave an animalistic growl that echoed and reverberated from within his protective suit, and broke through General Titus's defence, breaking the man's sword in half, and sending the Roman flying across the chamber. He landed at the feet of his men. The other Romans looked upon the body of their leader—crumpled, broken, defeated—and a look of determination fell across all their faces. They loved him, and they would die for him, as he had done for them; that much was clear.

The Kuricam fell to the floor, and as it picked itself up, Romana noticed a crack right across its lens. Its legs were shaking more than ever—with anger now, not just at the weight of its body. "Resistance will _not_ be tolerated," it said defiantly.

A young female Roman soldier bent down and searched Titus' body. Eventually, her hand found his radio. She spoke into it: "Bomber Command, do you read me? General Titus has fallen. The manipulators of reality will pay for this outrage." She paused, taking a deep breath.

The Doctor, as if suddenly realising she was about to do, rushed over to her. Hands outstretched, he tried to grab the radio from her. But he wasn't fast enough. "No, wait—"

"Bring this place down," finished the Roman. "Leave nothing standing, and no one alive."

"Don't!" cried the Doctor angrily.

Romana rushed over to join him. "Why would you do that?" she asked the female soldier. "We can end this peacefully, not with bloodshed!"

"From the moment the Cavalier came to us for aid," the Roman soldier explained, "we knew that were destined to die. As he explained, our existence is _wrong_. The Zeronaughts have warped and twisted us for their own ill purpose. We are willing to give our lives to end theirs. Now, soldiers, charge! For Rome!"

"For Rome!" the soldiers echoed in a mighty roar.

The Romans moved forward as a unit, pushing past the Doctor and Romana, drawing their swords, ready for battle.

The single Kuricam—bureaucratic and ridiculous yet undeniably brave—jumped up onto the woman's shoulder. Its broken lens glowed with a blue light, as it readied itself to re-join the battle.

The Zeronaughts advanced as well, leaving their workstations for the first time to defend their place of work—their home. Their clenched fists glowed with improbably potent energy. Nil stood firm at the front, while Zilch cowered at the back. He was only a scientist; he had never signed on for this.

The Doctor, Romana, the Cavalier and K-9 all dived out of the way as the two armies clashed. The clang of steel against metal sliced through the air, while distant, terrible rumbles could be heard from outside.

"Please, all of you, listen to us!" cried Romana, shouting to be heard over the chaos. "Stop this! We have to leave _now_, or we'll all be killed!"

K-9's ears twitched nervously.

"It's all right, boy," said the Doctor reassuringly. "Even if no one else is, _we_ are leaving." Apparently noticing the look of horror on Romana's face, he continued, "There's nothing else we can do. I'm sorry. Everyone, to the TARDIS!"


	15. Chapter Fifteen

The Fear of All Sums

By Samuel Marks

Chapter Fifteen

The Doctor led his friends across the chamber, dodging rubble that fell from the ceiling, swords that were thrust out of the crowd, and bursts of energy that flew past them. The battle raged all around.

He fumbled for the TARDIS key, eventually finding it. K-9 trundled in first as the door was unlocked. But when the Doctor looked around for the Cavalier, he was nowhere to be seen.

"Cavalier?" cried the Doctor.

"Where are you?" asked Romana.

They watched as, out of the chaos, Nil the Calculator stepped forwards, with the Cavalier in his grasp. The Zeronaught's hand shone with a terrible light: he was going to kill the Time Lord.

"Hand him over," said the Doctor. "There's no need to kill him."

"You brought down our empire," said Nil, "and this man helped you. Together, you challenged us. There is _every_ need to kill him."

The Doctor's steely façade cracked. "Please. Don't, I beg you. Just don't."

The Zeronaught held his glowing hand against the Cavalier's hearts, and the Time Lord cried out in pain. Nil chuckled at the screams, and then decided to stop torturing his prisoner. He seemed to have more to say.

"Our machine lies in ruins, as everything we have ever worked for crumbles around it—around us. Tell me, Doctor, what happens when it completely shuts down?"

"The Zeronaughts' hold on reality is broken. Time snaps back into place. Everything you wronged will be righted. Rome becomes ancient again, and all the other changes that rippled out of that are undone. It's as simple as that. If a stone is never dropped into the water, there aren't any ripples. Normality resumes."

"And we die," finished the Zeronaught grimly.

The Doctor nodded sadly. "I'm sorry. You were brilliant men. You could've done wonders for the universe. You just chose the wrong path, that's all. It's all about decisions. Please, as your last act, don't make another bad one. Let the Cavalier go."

Reluctantly, Nil threw the Cavalier forward, into the Doctor's arms. The Cavalier could barely support the weight of his own body; his legs buckled beneath him.

"Into the TARDIS, you two," the Doctor ordered.

Romana helped the injured Cavalier inside. He was still wincing, as if the pain had never stopped, even when the Zeronaught had released him.

"I may be willing to let your friends live," said Nil, as his fist glowed brighter, "but you, Doctor, destroyed everything we have worked so hard for. You cannot survive past this day. Say your prayers."

The Doctor smiled darkly. "You worked out all the answers to the big questions. You know the secrets of the universe, the truth about the Creators and the Destroyers, and God himself... Why would _I_ pray?"

The Zeronaught raised his hand, ready to kill.

The Doctor closed his eyes, ready to die. "My friends are safe," he said. "And you are not. At the end, then, I can be happy."

But suddenly, a harsh white light hit Nil the Calculator from behind, killing the glow of his hand and knocking him to the floor. The Doctor squeezed an eye open, daring to look.

The Kuricam leapt up onto Nil's back, and nodded at the Doctor. "He will be arrested and punished. Justice will be swift. We will take him from this place. Death is not a valid excuse."

The Doctor smiled and nodded back. "Quite right too."

"Curse you, Doctor!" cried Nil, unable to move. "But know this: soon—sooner than you think, Time Lord—_you will fall_."

"I understand. Everything ends." The Doctor looked at his own hands. They were not as young as they once were; he saw that they were old man's hands, and suddenly he became aware that he was looking at them out of old man's eyes. "Yes, I suppose... It's about time."

With that, he Kuricam and the Zeronaught disappeared in the blink of an eye.

The Doctor took a final look at the chaos, and the few remaining Romans who still fought against the black-clad scientists. He glanced over at the Zeronaughts' machine, as it shook violently and smoke poured out of it. It was broken, useless, failing.

He gave a sigh of relief: this was all going to end. The false reality that the Zeronaughts' had created would buckle under the weight of its own improbability without the machine in place to sustain it. Time would revert back to how it should be. Technologies would return to their own time, and all would be well once again.

The Doctor stepped inside the TARDIS.

In the control room, the Doctor was surprised to see the Cavalier on the floor, clutching his chest in agony. Romana was knelt down, examining him. The Doctor joined her.

"What happened?" he asked, alarmed.

"I think that Zeronaughts' energy," Romana said, "had already started to kill him. A lot of damage was already done to his hearts. Maybe _enough_ damage to—"

"No!" said the Doctor, grief-stricken. "Cavalier, hold on! Do you hear me? What can we do? Romana, help me! What do we need?"

"I need..." said the Cavalier, like it was painful to even talk. "I need, Doctor... to go home. To see it, one last time, before I—"

"Don't say it," said the Doctor.

"Nothing lasts for ever." The Cavalier winced. "It all ends."

"But not this," the Doctor replied. "Not _us_..."

Romana was at the console, programming in co-ordinates. It was clear that she didn't want to go back, but they had to. Though the Doctor might refuse to admit it, this was to Cavalier's final wish—his last request.

"To Gallifrey," she said sadly, under her breath.


	16. Chapter Sixteen

The Fear of All Sums

By Samuel Marks

Chapter Sixteen

Romana watched with tears in her eyes as the Doctor carried his old friend, the Cavalier, out of the TARDIS. As if sensing that something was wrong, the time machine had been strangely compliant during the flight, and had brought them to Gallifrey with no turbulence, no delays, no complications.

K-9 remained inside the police box, now wired up to the console to restore his power after recent events had left him weak. He would be back to normal in no time at all. The same could not, however, be said of the Cavalier.

The TARDIS had landed at the summit of the snowy Mount Solitude. Snowflakes tumbled majestically out of the sky, already beginning to settle on the roof of the police box. The Doctor placed the Cavalier down on the snow-capped field of deep red grass. Romana knelt down beside him and checked his condition. Despite the warmth in the air, as the first sun was setting and the second was rising in the south, the Cavalier was shivering; his hearts were beating rapidly, trying to keep his body going, desperately clinging onto life.

He didn't want to die. But then again, no one ever did.

The Doctor hadn't spoken in a long while. Romana looked up at him, but didn't expect to see a tear run down his cheek. He so rarely told her what he was really feeling that it unsettled her to see such an open display of emotion. He usually acted so strong and tough. But it was exactly that: an act.

While Romana felt terribly sad at the death of the Cavalier—a great man whom she had only met that day—she supposed that the Doctor must have been feeling a hundred times worse than her. This was, after all, one of his oldest and closest friends. He may not have spoken to him, or even _about _him, in a very long time, but Romana could still picture the look of delight on the Doctor face when his friend's name had been mentioned, when he thought that he might get to see him again.

The Cavalier summoned just enough strength to turn his head to the side. Between this mountain and Mount Solace in the distance was the Citadel of the Time Lords. A smile crept out across his face. Though they had expelled him and forced him to live a life of exile, it seemed that the Cavalier was still happy to be near to his people in his final moments.

Finally, the Doctor spoke out. "Don't die," he said, as his voice cracked. "Can you remember all those days we spent together in our youth? We were only a few decades old. Hold on to those memories. Sitting on these hills, in the shadow of the Citadel, you and me and the rest of the gang. The Corsair! Remember him? And _her_, sometimes? And the Master, always causing trouble! Some things never change, eh?" He smiled at the beautiful, distant memories. "We dreamed of this life, Cavalier, to go sailing out among the stars, to see the great wide universe in all its majesty. And we made it. We lived the dream. Don't wake up now, not yet. Stay with me."

"You know the rules, Doctor," replied the Cavalier. "Those silly old rules. Thirteen lives, and that's your lot."

The Doctor looked over at Romana. He seemed so lost, so helpless. He seemed expectant, like he was waiting for her to speak up, to confirm what he was thinking. They were so in sync, and were having the same thoughts, coming up with the same ridiculous plan.

"I think... It's not a biological restraint," Romana said, trying to sound confident when she really wasn't. But it was what the Doctor wanted to hear—what he _needed_ to hear. "Your body_ could_ survive indefinitely. The limit is imposed and maintained by the Time Lords. Without them there to monitor the changes, to uphold the rules of regeneration, them you could, in theory, live for ever."

The tears began to clear from the Doctor's eyes, as hope filled his face. "Hear that?" he said to the Cavalier. "I could talk to the others at the Citadel. They'd listen to me—I'm the Lord President! They might let me make an exception, for you."

The Cavalier winced in pain. Romana took hold of his hand, willing him to fight it, to stay strong. "I'm an exile, Doctor. As far as they're concerned, I'm already dead."

"Let me _try_!" the Doctor said desperately.

The Cavalier shook his head. He cried out in pain—such terrible pain.

Suddenly, Romana pulled her hand away, as the Cavalier's skin burnt hers. He was hot to the touch. A warm glow illuminated his skin, as an intense white light shone out from beneath his skin, from deep within. His body was capable of saving itself, and it was determined not to relinquish its hold on life.

But the Time Lords had other ideas: in an instant, the light died away. The Doctor stared down at the lifeless body of his friend. Romana wiped the tears from her face, only for them to be replaced seconds later.

The Cavalier was dead.

"The regeneration was beginning," said the Doctor, not taking his eyes off the body. "The process had started, before it was cut short. He could have saved himself. He could have lived again. A fourteenth body and so many others afterwards..."

He looked up at Romana, and his face was streaked with tears. "He's dead because of _them_." He jabbed a finger in the direction of the Citadel. "You see now why I left? You see why we're never coming back? They think they have the right to control life and death, to decide who lives and who dies. And that's _wrong_!"

Romana reached out and took the Doctor's hand. They both held onto each other, so tight.

"It's just you and me, Romana," said the Doctor, forcing a sad smile. He looked so old and tired, and so alone. He let go of her hand. Romana opened her mouth to say something—anything that she thought might comfort her friend—but the Doctor spoke up again first.

"Can you get the TARDIS ready?" he asked, regaining his composure. "We'll be leaving in a moment. I want a few minutes alone with the Cavalier. Is that okay?"

Romana wouldn't refuse. She nodded, picked herself up off the grass, and headed towards the TARDIS. When she reached the doors of the police box, she turned around and saw the Doctor sobbing gently over the Cavalier's body. She didn't hear what he was saying, and she respected his wishes enough not to ask. If he wanted her to know, he would tell her.

He never did.

Romana had busied herself at the console, waiting for the Doctor to return. He was gone for some time. Hearing the creak of the door, she looked up and saw the Doctor, covered in snow, wandering back into the control room. He seemed to be deliberately avoiding eye contact with her.

He absent-mindedly flicked a random switch on the console, and exhaled loudly, as if that might relieve the tension and the pressure. Romana thought about making the first move, wondering if she should speak up. But she struggled to think of what she should say—what she _could_ say—to a man who was still emotionally raw from a tragic loss.

"K-9's in the games room," she said feebly. "He's waiting for you. He said, after the day you've had, he might even go easy on you."

The Doctor smiled, though it was tainted by sadness.

"Are we just going to leave the Cavalier out there?" asked Romana. It was indiscreet, but she couldn't contain her worries any longer.

"The snow will bury him. His body will become part of the natural world, part of the magical landscape of Gallifrey itself. Untainted. Uncorrupted. It's better than handing him over to the Time Lords. Where he is, he can rest in peace."

The Doctor threw a lever, and the scanner screen peeled away to reveal to view outside, of the Cavalier's body now half-buried in the snow.

"This view," he said. "I'll never forget it."

Romana just nodded. He may always remember it, but it would be for the wrong reason, forever reminding him of the death of his friend.

The Doctor bowed his head again, seemingly overcome by the sadness. Noticing this, Romana reached across, flicked the lever the other way, closing the scanner. The image slowly disappeared, until the Cavalier was gone.

Romana clapped her hands together decisively, trying to snap the Doctor out of his stupor. "So," she said, "where next? We can take this old TARDIS anywhere you like. What do you think, Doctor?"

"I think," the Doctor replied, "that you should take over flying for a while." He headed for the corridor to the rest of the TARDIS.

Before he disappeared into the deep darkness of the rest of the ship, Romana called out to him. "It'll be okay, Doctor," she said reassuringly. "You'll get past this."

"Oh, Romana," he said. "Of all the things we've seen today, that's the only thing that's truly impossible."

He turned a corner, and then he was gone. Romana looked up at the time rotor, as it began its steady rise and fall. She started to cry again, and knew in her hearts that the Doctor was doing the same.


	17. Chapter Seventeen - The End

The Fear of All Sums

By Samuel Marks

Chapter Seventeen

Zilch found himself lying flat on his face in the thick snow. He tried to clamber to his feet, which wasn't easy and took several attempts, as he was within the confines of his heavy mechanical suit, and his hands were bound in cuffs. Eventually he stood up, knee-deep in snow, and looked around.

"I did it!" he cried out, laughing excitedly. "I actually did it! Even without our machine, I worked out the equation to get us to Gallifrey!"

By his side, a Kuricam appeared in a teleport glow. "Your assistance is appreciated," it said, as it began to trudge through the snow. Its thin, mechanical legs struggled to carry it across the wintry landscape. "Keep up, prisoner."

Zilch nodded, and followed the Kuricam. "I knew I could do it. Everyone always said I was stupid, that I was always so easily distracted, but—oh, it's snowing!"

"The target is nearby," declared the Kuricam.

"I _am_ good, though," Zilch went on. "I'm smarter than anyone ever gave me credit for—" Suddenly Zilch tripped over his own feet and collapsed onto the snow again.

"You are quite the genius indeed," the Kuricam replied, its tinny voice dripping artificial sarcasm. "Scan beginning in five, four, three, two, one..."

Zilch picked himself up, again with great difficulty, and turned his attention to the Kuricam.

The Kuricam channelled all its power to its laser circuitry. It strained as it extrapolated its body heat and radiated energy outwards. Its body sparked with electricity, as it used all its back-up power and emergency resources to melt the surrounding snow.

A body began to reveal itself, still and lifeless, but every inch the person that the Kuricam had been searching for.

"It's him! That's the Cavalier!" Zilch realised. He approached the man's body, and knelt down beside it. "He's dead," he announced gravely. "No regeneration. He's gone."

"Death is not a valid excuse. The Cavalier must be punished for his crimes." A light exploded out from the Kuricam's lens, as it scanned the lifeless body once again. "Capacity for regeneration still exists."

"So I brought you here like you asked, but why? What are you lot planning?"

"Justice will be swift," the Kuricam said. "Resurrection may take longer."

ARCHAEOLOGIST'S DISCOVERY LEADS TO FAME AND FORTUNE declared the newspaper headline. Romana smiled to herself, as history was back on track. She continued to flick through the paper, while people played and frolicked in the park around her.

The sun was hidden behind a thick layer of cloud, but the air seemed cool and pleasant. It had been raining recently, and would no doubt rain again, but everyone was enjoying the brief moment of calm.

Romana sighed contently. "This is nice," she said to herself. As a tennis ball came hurtling towards her head, she reached out and caught it without looking.

"Nice catch!" shouted the Doctor. He made his way over to her, and sat down beside her on the bench.

Romana handed him the tennis ball. "I don't know why you're bothering," she said. "He's back to his old self, and he'll never change again."

"More's the pity," replied the Doctor miserably. "We can't do any throwing and catching games now. Watch this."

The Doctor hurled the ball across the park towards K-9, who was parked, still and motionless. The robot dog didn't react at all when the tennis ball hit him in the side with a great metallic thump.

"He can't even move on the grass." The Doctor chuckled to himself, and then noticed what Romana was reading. He indicated the paper. "Any news?"

"Nothing bad," she replied. "Nothing that breaks the laws of physics. Everything's like it used to be." She hoped so, anyway.

"That's a bit of a shame," sighed the Doctor. "It's quiet. Far too quiet for me."

"Gives you plenty of time to be alone with your thoughts."

"Exactly." There was a sad look in the Doctor's eyes. Suddenly, he stood up and stared across the park. "Is that...?"

Romana didn't look up from the newspaper. "What's wrong?"

"N-nothing," the Doctor replied. His voice was shaky, uncertain. "Nothing's _wrong_, exactly. Romana, look!"

She did as she was told, and looked to where the Doctor was pointing. Between the trees, cloaked in shadow, she saw a man. He began to walk towards them, and as he got closer, Romana could just about make out his face. His eyes were so familiar.

"That's impossible," Romana said.

The Doctor wore the biggest grin. "No. Just improbable."

THE END


End file.
